Muda, Lindasalwa; Elamvazuthi, I
2010-01-01
Digital processing of speech signal and voice recognition algorithm is very important for fast and accurate automatic voice recognition technology. The voice is a signal of infinite information. A direct analysis and synthesizing the complex voice signal is due to too much information contained in the signal. Therefore the digital signal processes such as Feature Extraction and Feature Matching are introduced to represent the voice signal. Several methods such as Liner Predictive Predictive Coding (LPC), Hidden Markov Model (HMM), Artificial Neural Network (ANN) and etc are evaluated with a view to identify a straight forward and effective method for voice signal. The extraction and matching process is implemented right after the Pre Processing or filtering signal is performed. The non-parametric method for modelling the human auditory perception system, Mel Frequency Cepstral Coefficients (MFCCs) are utilize as extraction techniques. The non linear sequence alignment known as Dynamic Time Warping (DTW) intro...
Spoken Utterance Detection Using Dynamic Time Warping Method Along With a Hashing Technique
Directory of Open Access Journals (Sweden)
John Sahaya Rani Alex
2014-05-01
Full Text Available This paper presents a technique of searching a keyword in a spoken utterance using Dynamic Programming algorithm. This method is being revisited because of the evolution in computing power. The proposed methods present less computational complexity compared with the conventional Dynamic Time Warping (DTW method. The proposed methods are tested with connected TIDIGIT data.
An HMM-Like Dynamic Time Warping Scheme for Automatic Speech Recognition
Directory of Open Access Journals (Sweden)
Ing-Jr Ding
2014-01-01
Full Text Available In the past, the kernel of automatic speech recognition (ASR is dynamic time warping (DTW, which is feature-based template matching and belongs to the category technique of dynamic programming (DP. Although DTW is an early developed ASR technique, DTW has been popular in lots of applications. DTW is playing an important role for the known Kinect-based gesture recognition application now. This paper proposed an intelligent speech recognition system using an improved DTW approach for multimedia and home automation services. The improved DTW presented in this work, called HMM-like DTW, is essentially a hidden Markov model- (HMM- like method where the concept of the typical HMM statistical model is brought into the design of DTW. The developed HMM-like DTW method, transforming feature-based DTW recognition into model-based DTW recognition, will be able to behave as the HMM recognition technique and therefore proposed HMM-like DTW with the HMM-like recognition model will have the capability to further perform model adaptation (also known as speaker adaptation. A series of experimental results in home automation-based multimedia access service environments demonstrated the superiority and effectiveness of the developed smart speech recognition system by HMM-like DTW.
Yuan, Yuan; Chen, Yi-Ping Phoebe; Ni, Shengyu; Xu, Augix Guohua; Tang, Lin; Vingron, Martin; Somel, Mehmet; Khaitovich, Philipp
2011-08-18
Comparing biological time series data across different conditions, or different specimens, is a common but still challenging task. Algorithms aligning two time series represent a valuable tool for such comparisons. While many powerful computation tools for time series alignment have been developed, they do not provide significance estimates for time shift measurements. Here, we present an extended version of the original DTW algorithm that allows us to determine the significance of time shift estimates in time series alignments, the DTW-Significance (DTW-S) algorithm. The DTW-S combines important properties of the original algorithm and other published time series alignment tools: DTW-S calculates the optimal alignment for each time point of each gene, it uses interpolated time points for time shift estimation, and it does not require alignment of the time-series end points. As a new feature, we implement a simulation procedure based on parameters estimated from real time series data, on a series-by-series basis, allowing us to determine the false positive rate (FPR) and the significance of the estimated time shift values. We assess the performance of our method using simulation data and real expression time series from two published primate brain expression datasets. Our results show that this method can provide accurate and robust time shift estimates for each time point on a gene-by-gene basis. Using these estimates, we are able to uncover novel features of the biological processes underlying human brain development and maturation. The DTW-S provides a convenient tool for calculating accurate and robust time shift estimates at each time point for each gene, based on time series data. The estimates can be used to uncover novel biological features of the system being studied. The DTW-S is freely available as an R package TimeShift at http://www.picb.ac.cn/Comparative/data.html.
Efficient Processing of Multiple DTW Queries in Time Series Databases
DEFF Research Database (Denmark)
Kremer, Hardy; Günnemann, Stephan; Ivanescu, Anca-Maria
2011-01-01
. In many of today’s applications, however, large numbers of queries arise at any given time. Existing DTW techniques do not process multiple DTW queries simultaneously, a serious limitation which slows down overall processing. In this paper, we propose an efficient processing approach for multiple DTW...... for multiple DTW queries....
Sign Language Recognition by Combining Statistical DTW and Independent Classification
Lichtenauer, J.F.; Hendriks,E.A; Reinders, M.J.T.
2008-01-01
To recognize speech, handwriting, or sign language, many hybrid approaches have been proposed that combine Dynamic Time Warping (DTW) or Hidden Markov Models (HMMs) with discriminative classifiers. However, all methods rely directly on the likelihood models of DTW/HMM. We hypothesize that time warpi
Energy Technology Data Exchange (ETDEWEB)
2017-04-12
WARP, which can stand for ``Weaving All the Random Particles,'' is a three-dimensional (3D) continuous energy Monte Carlo neutron transport code developed at UC Berkeley to efficiently execute on NVIDIA graphics processing unit (GPU) platforms. WARP accelerates Monte Carlo simulations while preserving the benefits of using the Monte Carlo method, namely, that very few physical and geometrical simplifications are applied. WARP is able to calculate multiplication factors, neutron flux distributions (in both space and energy), and fission source distributions for time-independent neutron transport problems. It can run in both criticality or fixed source modes, but fixed source mode is currently not robust, optimized, or maintained in the newest version. WARP can transport neutrons in unrestricted arrangements of parallelepipeds, hexagonal prisms, cylinders, and spheres. The goal of developing WARP is to investigate algorithms that can grow into a full-featured, continuous energy, Monte Carlo neutron transport code that is accelerated by running on GPUs. The crux of the effort is to make Monte Carlo calculations faster while producing accurate results. Modern supercomputers are commonly being built with GPU coprocessor cards in their nodes to increase their computational efficiency and performance. GPUs execute efficiently on data-parallel problems, but most CPU codes, including those for Monte Carlo neutral particle transport, are predominantly task-parallel. WARP uses a data-parallel neutron transport algorithm to take advantage of the computing power GPUs offer.
Directory of Open Access Journals (Sweden)
Martin eDinov
2016-05-01
Full Text Available Dynamic time warping, or DTW, is a powerful and domain-general sequence alignment method for computing a similarity measure. Such dynamic programming-based techniques like DTW are now the backbone and driver of most bioinformatics methods and discoveries. In neuroscience it has had far less use, though this has begun to change. We wanted to explore new ways of applying DTW, not simply as a measure with which to cluster or compare similarity between features but in a conceptually different way. We have used DTW to provide a more interpretable spectral description of the data, compared to standard approaches such as the Fourier and related transforms. The DTW approach and standard discrete Fourier transform (DFT are assessed against benchmark measures of neural dynamics. These include EEG microstates, EEG avalanches and the sum squared error (SSE from a multilayer perceptron (MLP prediction of the EEG timeseries, and simultaneously acquired FMRI BOLD signal. We explored the relationships between these variables of interest in an EEG-FMRI dataset acquired during a standard cognitive task, which allowed us to explore how DTW differentially performs in different task settings. We found that despite strong correlations between DTW and DFT-spectra, DTW was a better predictor for almost every measure of brain dynamics. Using these DTW measures, we show that predictability is almost always higher in task than in rest states, which is consistent to other theoretical and empirical findings, providing additional evidence for the utility of the DTW approach.
The DTW-based representation space for seismic pattern classification
Orozco-Alzate, Mauricio; Castro-Cabrera, Paola Alexandra; Bicego, Manuele; Londoño-Bonilla, John Makario
2015-12-01
Distinguishing among the different seismic volcanic patterns is still one of the most important and labor-intensive tasks for volcano monitoring. This task could be lightened and made free from subjective bias by using automatic classification techniques. In this context, a core but often overlooked issue is the choice of an appropriate representation of the data to be classified. Recently, it has been suggested that using a relative representation (i.e. proximities, namely dissimilarities on pairs of objects) instead of an absolute one (i.e. features, namely measurements on single objects) is advantageous to exploit the relational information contained in the dissimilarities to derive highly discriminant vector spaces, where any classifier can be used. According to that motivation, this paper investigates the suitability of a dynamic time warping (DTW) dissimilarity-based vector representation for the classification of seismic patterns. Results show the usefulness of such a representation in the seismic pattern classification scenario, including analyses of potential benefits from recent advances in the dissimilarity-based paradigm such as the proper selection of representation sets and the combination of different dissimilarity representations that might be available for the same data.
Automatic Inspection of the Warp-Weft Density Using Image Processing Techniques
ALDEMİR, Erdoğan; Hakan ÖZDEMİR; KILINÇ, Selçuk
2016-01-01
In this study, possibility of determining warp and weft yarn density of colored and figured plain and twill woven fabrics by Wiener filter, median filter, grey level co-occurrence matrix and gray line profile methods, which are spatial techniques, and by Fourier and wavelet transformation methods, which are frequency domain techniques, are investigated. Considering the spatial techniques, the most successful technique that determines warp and weft densities of plain and twill fabrics is the m...
Comparison of HMM and DTW methods in automatic recognition of pathological phoneme pronunciation
Wielgat, Robert; Zielinski, Tomasz P.; Swietojanski, Pawel; Zoladz, Piotr; Król, Daniel; Wozniak, Tomasz; Grabias, Stanislaw
2007-01-01
In the paper recently proposed Human Factor Cepstral Coefficients (HFCC) are used to automatic recognition of pathological phoneme pronunciation in speech of impaired children and efficiency of this approach is compared to application of the standard Mel-Frequency Cepstral Coefficients (MFCC) as a feature vector. Both dynamic time warping (DTW), working on whole words or embedded phoneme patterns, and hidden Markov models (HMM) are used as classifiers in the presented research. Obtained resul...
Improvements on EMG-based handwriting recognition with DTW algorithm.
Li, Chengzhang; Ma, Zheren; Yao, Lin; Zhang, Dingguo
2013-01-01
Previous works have shown that Dynamic Time Warping (DTW) algorithm is a proper method of feature extraction for electromyography (EMG)-based handwriting recognition. In this paper, several modifications are proposed to improve the classification process and enhance recognition accuracy. A two-phase template making approach has been introduced to generate templates with more salient features, and modified Mahalanobis Distance (mMD) approach is used to replace Euclidean Distance (ED) in order to minimize the interclass variance. To validate the effectiveness of such modifications, experiments were conducted, in which four subjects wrote lowercase letters at a normal speed and four-channel EMG signals from forearms were recorded. Results of offline analysis show that the improvements increased the average recognition accuracy by 9.20%.
Kogan, J A; Margoliash, D
1998-04-01
The performance of two techniques is compared for automated recognition of bird song units from continuous recordings. The advantages and limitations of dynamic time warping (DTW) and hidden Markov models (HMMs) are evaluated on a large database of male songs of zebra finches (Taeniopygia guttata) and indigo buntings (Passerina cyanea), which have different types of vocalizations and have been recorded under different laboratory conditions. Depending on the quality of recordings and complexity of song, the DTW-based technique gives excellent to satisfactory performance. Under challenging conditions such as noisy recordings or presence of confusing short-duration calls, good performance of the DTW-based technique requires careful selection of templates that may demand expert knowledge. Because HMMs are trained, equivalent or even better performance of HMMs can be achieved based only on segmentation and labeling of constituent vocalizations, albeit with many more training examples than DTW templates. One weakness in HMM performance is the misclassification of short-duration vocalizations or song units with more variable structure (e.g., some calls, and syllables of plastic songs). To address these and other limitations, new approaches for analyzing bird vocalizations are discussed.
Cough Recognition Based on Mel Frequency Cepstral Coefficients and Dynamic Time Warping
Zhu, Chunmei; Liu, Baojun; Li, Ping
Cough recognition provides important clinical information for the treatment of many respiratory diseases, but the assessment of cough frequency over a long period of time remains unsatisfied for either clinical or research purpose. In this paper, according to the advantage of dynamic time warping (DTW) and the characteristic of cough recognition, an attempt is made to adapt DTW as the recognition algorithm for cough recognition. The process of cough recognition based on mel frequency cepstral coefficients (MFCC) and DTW is introduced. Experiment results of testing samples from 3 subjects show that acceptable performances of cough recognition are obtained by DTW with a small training set.
Fault diagnosis of motor drives using stator current signal analysis based on dynamic time warping
Zhen, D.; Wang, T.; Gu, F.; Ball, A. D.
2013-01-01
Electrical motor stator current signals have been widely used to monitor the condition of induction machines and their downstream mechanical equipment. The key technique used for current signal analysis is based on Fourier transform (FT) to extract weak fault sideband components from signals predominated with supply frequency component and its higher order harmonics. However, the FT based method has limitations such as spectral leakage and aliasing, leading to significant errors in estimating the sideband components. Therefore, this paper presents the use of dynamic time warping (DTW) to process the motor current signals for detecting and quantifying common faults in a downstream two-stage reciprocating compressor. DTW is a time domain based method and its algorithm is simple and easy to be embedded into real-time devices. In this study DTW is used to suppress the supply frequency component and highlight the sideband components based on the introduction of a reference signal which has the same frequency component as that of the supply power. Moreover, a sliding window is designed to process the raw signal using DTW frame by frame for effective calculation. Based on the proposed method, the stator current signals measured from the compressor induced with different common faults and under different loads are analysed for fault diagnosis. Results show that DTW based on residual signal analysis through the introduction of a reference signal allows the supply components to be suppressed well so that the fault related sideband components are highlighted for obtaining accurate fault detection and diagnosis results. In particular, the root mean square (RMS) values of the residual signal can indicate the differences between the healthy case and different faults under varying discharge pressures. It provides an effective and easy approach to the analysis of motor current signals for better fault diagnosis of the downstream mechanical equipment of motor drives in the time
Merge-Weighted Dynamic Time Warping for Speech Recognition
Institute of Scientific and Technical Information of China (English)
张湘莉兰; 骆志刚; 李明
2014-01-01
Obtaining training material for rarely used English words and common given names from countries where English is not spoken is diﬃcult due to excessive time, storage and cost factors. By considering personal privacy, language-independent (LI) with lightweight speaker-dependent (SD) automatic speech recognition (ASR) is a convenient option to solve the problem. The dynamic time warping (DTW) algorithm is the state-of-the-art algorithm for small-footprint SD ASR for real-time applications with limited storage and small vocabularies. These applications include voice dialing on mobile devices, menu-driven recognition, and voice control on vehicles and robotics. However, traditional DTW has several limitations, such as high computational complexity, constraint induced coarse approximation, and inaccuracy problems. In this paper, we introduce the merge-weighted dynamic time warping (MWDTW) algorithm. This method defines a template confidence index for measuring the similarity between merged training data and testing data, while following the core DTW process. MWDTW is simple, eﬃcient, and easy to implement. With extensive experiments on three representative SD speech recognition datasets, we demonstrate that our method outperforms DTW, DTW on merged speech data, the hidden Markov model (HMM) significantly, and is also six times faster than DTW overall.
Perceived Speech Quality Estimation Using DTW Algorithm
Directory of Open Access Journals (Sweden)
S. Arsenovski
2009-06-01
Full Text Available In this paper a method for speech quality estimation is evaluated by simulating the transfer of speech over packet switched and mobile networks. The proposed system uses Dynamic Time Warping algorithm for test and received speech comparison. Several tests have been made on a test speech sample of a single speaker with simulated packet (frame loss effects on the perceived speech. The achieved results have been compared with measured PESQ values on the used transmission channel and their correlation has been observed.
Knuth, Martin; Bender, Jan; Goesele, Michael; Kuijper, Arjan
2016-03-18
We introduce deferred warping, a novel approach for real-time deformation of 3D objects attached to an animated or manipulated surface. Our target application is virtual prototyping of garments where 2D pattern modeling is combined with 3D garment simulation which allows an immediate validation of the design. The technique works in two steps: First, the surface deformation of the target object is determined and the resulting transformation field is stored as a matrix texture. Then the matrix texture is used as look-up table to transform a given geometry onto a deformed surface. Splitting the process in two steps yields a large flexibility since different attachment types can be realized by simply defining specific mapping functions. Our technique can directly handle complex topology changes within the surface. We demonstrate a fast implementation in the vertex shading stage allowing the use of highly decorated surfaces with millions of triangles in real-time.
Dynamic time warping: A new method in the study of poor handwriting
Brina, C. di; Niels, R.M.J.; Overvelde, A.J.A.A.M.; Levi, G.; Hulstijn, W.
2008-01-01
Poor handwriting is a diagnostic criterion for developmental coordination disorder. Typical of poor handwriting is its low overall quality and the high variability of the spatial characteristics of the letters, usually assessed with a subjective handwriting scale. Recently, Dynamic Time Warping (DTW
Directory of Open Access Journals (Sweden)
Xudong Guan
2016-01-01
Full Text Available Normalized Difference Vegetation Index (NDVI derived from Moderate Resolution Imaging Spectroradiometer (MODIS time-series data has been widely used in the fields of crop and rice classification. The cloudy and rainy weather characteristics of the monsoon season greatly reduce the likelihood of obtaining high-quality optical remote sensing images. In addition, the diverse crop-planting system in Vietnam also hinders the comparison of NDVI among different crop stages. To address these problems, we apply a Dynamic Time Warping (DTW distance-based similarity measure approach and use the entire yearly NDVI time series to reduce the inaccuracy of classification using a single image. We first de-noise the NDVI time series using S-G filtering based on the TIMESAT software. Then, a standard NDVI time-series base for rice growth is established based on field survey data and Google Earth sample data. NDVI time-series data for each pixel are constructed and the DTW distance with the standard rice growth NDVI time series is calculated. Then, we apply thresholds to extract rice growth areas. A qualitative assessment using statistical data and a spatial assessment using sampled data from the rice-cropping map reveal a high mapping accuracy at the national scale between the statistical data, with the corresponding R2 being as high as 0.809; however, the mapped rice accuracy decreased at the provincial scale due to the reduced number of rice planting areas per province. An analysis of the results indicates that the 500-m resolution MODIS data are limited in terms of mapping scattered rice parcels. The results demonstrate that the DTW-based similarity measure of the NDVI time series can be effectively used to map large-area rice cropping systems with diverse cultivation processes.
Dynamic Time Warping Distance Method for Similarity Test of Multipoint Ground Motion Field
Directory of Open Access Journals (Sweden)
Yingmin Li
2010-01-01
Full Text Available The reasonability of artificial multi-point ground motions and the identification of abnormal records in seismic array observations, are two important issues in application and analysis of multi-point ground motion fields. Based on the dynamic time warping (DTW distance method, this paper discusses the application of similarity measurement in the similarity analysis of simulated multi-point ground motions and the actual seismic array records. Analysis results show that the DTW distance method not only can quantitatively reflect the similarity of simulated ground motion field, but also offers advantages in clustering analysis and singularity recognition of actual multi-point ground motion field.
Instantaneous and Frequency-Warped Signal Processing Techniques for Auditory Source Separation.
Wang, Avery Li-Chun
This thesis summarizes several contributions to the areas of signal processing and auditory source separation. The philosophy of Frequency-Warped Signal Processing is introduced as a means for separating the AM and FM contributions to the bandwidth of a complex-valued, frequency-varying sinusoid p (n), transforming it into a signal with slowly-varying parameters. This transformation facilitates the removal of p (n) from an additive mixture while minimizing the amount of damage done to other signal components. The average winding rate of a complex-valued phasor is explored as an estimate of the instantaneous frequency. Theorems are provided showing the robustness of this measure. To implement frequency tracking, a Frequency-Locked Loop algorithm is introduced which uses the complex winding error to update its frequency estimate. The input signal is dynamically demodulated and filtered to extract the envelope. This envelope may then be remodulated to reconstruct the target partial, which may be subtracted from the original signal mixture to yield a new, quickly-adapting form of notch filtering. Enhancements to the basic tracker are made which, under certain conditions, attain the Cramer -Rao bound for the instantaneous frequency estimate. To improve tracking, the novel idea of Harmonic -Locked Loop tracking, using N harmonically constrained trackers, is introduced for tracking signals, such as voices and certain musical instruments. The estimated fundamental frequency is computed from a maximum-likelihood weighting of the N tracking estimates, making it highly robust. The result is that harmonic signals, such as voices, can be isolated from complex mixtures in the presence of other spectrally overlapping signals. Additionally, since phase information is preserved, the resynthesized harmonic signals may be removed from the original mixtures with relatively little damage to the residual signal. Finally, a new methodology is given for designing linear-phase FIR filters
Energy Technology Data Exchange (ETDEWEB)
2016-10-25
Sirepo is an open source framework for cloud computing. The graphical user interface (GUI) for Sirepo, also known as the client, executes in any HTML5 compliant web browser on any computing platform, including tablets. The client is built in JavaScript, making use of the following open source libraries: Bootstrap, which is fundamental for cross-platform web applications; AngularJS, which provides a model–view–controller (MVC) architecture and GUI components; and D3.js, which provides interactive plots and data-driven transformations. The Sirepo server is built on the following Python technologies: Flask, which is a lightweight framework for web development; Jin-ja, which is a secure and widely used templating language; and Werkzeug, a utility library that is compliant with the WSGI standard. We use Nginx as the HTTP server and proxy, which provides a scalable event-driven architecture. The physics codes supported by Sirepo execute inside a Docker container. One of the codes supported by Sirepo is Warp. Warp is a particle-in-cell (PIC) code de-signed to simulate high-intensity charged particle beams and plasmas in both the electrostatic and electromagnetic regimes, with a wide variety of integrated physics models and diagnostics. At pre-sent, Sirepo supports a small subset of Warp’s capabilities. Warp is open source and is part of the Berkeley Lab Accelerator Simulation Toolkit.
Gain, James; Marais, Patrick
2005-01-01
The task of computer-based free-form shape design is fraught with practical and conceptual difficulties. Incorporating elements of traditional clay sculpting has long been recognized as a means of shielding the user from these complexities. We present warp sculpting, a variant of spatial deformation, which allows deformations to be initiated by the rigid body transformation or uniform scaling of volumetric tools. This is reminiscent of a tool imprinting, flexing, and molding clay. Unlike previous approaches, the deformation is truly interactive. Tools, encoded in a distance field, can have arbitrarily complex shapes. Although individual tools have a static shape, several tools can be applied simultaneously. We enhance the basic formulation of warp sculpting in two ways. First, deformation is toggled to automatically overcome the problem of "sticky" tools, where the object's surface clings to parts of a tool that are moving away. Second, unlike many other spatial deformations, we ensure that warp sculpting remains foldover-free and, hence, prevent self-intersecting objects.
Kale, Nimish; Lee, Jaeseong; Lotfian, Reza; Jafari, Roozbeh
2012-10-01
Daily living activity monitoring is important for early detection of the onset of many diseases and for improving quality of life especially in elderly. A wireless wearable network of inertial sensor nodes can be used to observe daily motions. Continuous stream of data generated by these sensor networks can be used to recognize the movements of interest. Dynamic Time Warping (DTW) is a widely used signal processing method for time-series pattern matching because of its robustness to variations in time and speed as opposed to other template matching methods. Despite this flexibility, for the application of activity recognition, DTW can only find the similarity between the template of a movement and the incoming samples, when the location and orientation of the sensor remains unchanged. Due to this restriction, small sensor misplacements can lead to a decrease in the classification accuracy. In this work, we adopt DTW distance as a feature for real-time detection of human daily activities like sit to stand in the presence of sensor misplacement. To measure this performance of DTW, we need to create a large number of sensor configurations while the sensors are rotated or misplaced. Creating a large number of closely spaced sensors is impractical. To address this problem, we use the marker based optical motion capture system and generate simulated inertial sensor data for different locations and orientations on the body. We study the performance of the DTW under these conditions to determine the worst-case sensor location variations that the algorithm can accommodate.
Energy Technology Data Exchange (ETDEWEB)
Lazik, Andrea; Lauenstein, Thomas C.; Theysohn, Jens M. [University Hospital Essen, Department of Diagnostic and Interventional Radiology and Neuroradiology, Essen (Germany); Landgraeber, Stefan; Schulte, Patrick [University Hospital Essen, Department of Orthopedics, Essen (Germany); Kraff, Oliver [University of Duisburg-Essen, Erwin L. Hahn Institute for Magnetic Resonance Imaging, Essen (Germany)
2015-03-25
To evaluate the usefulness of the metal artifact reduction technique ''WARP'' in the assessment of metal-on-metal hip resurfacings at 1.5 and 3T in the context of image quality and imaging speed. Nineteen patients (25 hip resurfacings) were randomized for 1.5 and 3T MRI, both including T1 and T2 turbo spin-echo as well as turbo inversion recovery magnitude sequences with and without view angle tilting and high bandwidth. Additional 3T sequences were acquired with a reduced number of averages and using the parallel acquisition technique for accelerating imaging speed. Artifact size (diameter, area), image quality (5-point scale) and delineation of anatomical structures were compared among the techniques, sequences and field strengths using the Wilcoxon sign-rank and paired t-test with Bonferroni correction. At both field strengths, WARP showed significant superiority over standard sequences regarding image quality, artifact size and delineation of anatomical structures. At 3T, artifacts were larger compared to 1.5T without affecting diagnostic quality, and scanning time could be reduced by up to 64 % without quality degradation. WARP proved useful in imaging metal-on-metal hip resurfacings at 1.5T as well as 3T with better image quality surrounding the implants. At 3T imaging could be considerably accelerated without losing diagnostic quality. (orig.)
Directory of Open Access Journals (Sweden)
Xianglilan Zhang
Full Text Available Considering personal privacy and difficulty of obtaining training material for many seldom used English words and (often non-English names, language-independent (LI with lightweight speaker-dependent (SD automatic speech recognition (ASR is a promising option to solve the problem. The dynamic time warping (DTW algorithm is the state-of-the-art algorithm for small foot-print SD ASR applications with limited storage space and small vocabulary, such as voice dialing on mobile devices, menu-driven recognition, and voice control on vehicles and robotics. Even though we have successfully developed two fast and accurate DTW variations for clean speech data, speech recognition for adverse conditions is still a big challenge. In order to improve recognition accuracy in noisy environment and bad recording conditions such as too high or low volume, we introduce a novel one-against-all weighted DTW (OAWDTW. This method defines a one-against-all index (OAI for each time frame of training data and applies the OAIs to the core DTW process. Given two speech signals, OAWDTW tunes their final alignment score by using OAI in the DTW process. Our method achieves better accuracies than DTW and merge-weighted DTW (MWDTW, as 6.97% relative reduction of error rate (RRER compared with DTW and 15.91% RRER compared with MWDTW are observed in our extensive experiments on one representative SD dataset of four speakers' recordings. To the best of our knowledge, OAWDTW approach is the first weighted DTW specially designed for speech data in adverse conditions.
Warp Drive - From Imagination to Reality
Gardiner, J.
The realisation of warp drive is far beyond current science and technology; nevertheless, setting out a timetable for the realisation of warp drive is instructive as this will set expectations for the progress of future research. It is proposed that a time scale for the realisation of warp drive can be estimated by historical analogy with the development of manned space travel to the Moon, using conventional project estimation techniques. A timeline for space travel to the Moon begins with Cyrano de Bergerac's Voyage dans la Lune in 1657 and culminates with the Apollo 11 Moon landing in 1969, a little over 300 years later. A similar timeline for warp drive begins with John W. Campbell's novel Islands of Space in 1930. Fictional conjecture on the warp drive has given way to serious scientific speculation following publication of Alcubierre's seminal warp drive paper in 1994. It is concluded that the realisation of warp drive might be achieved around the year 2180. A projected timetable for the realisation of warp drive through phases of conjecture , speculation , science , technology and application suggests that the warp drive proposal should enter the science phase around the year 2030.
He, Chenxu; Wylie, William
2011-01-01
In this paper we study the space of solutions to an overdetermined linear system involving the Hessian of functions. We show that if the solution space has dimension greater than one, then the underlying manifold has a very rigid warped product structure. This warped product structure will be used to study warped product Einstein structures in our paper "The space of virtual solutions to the warped product Einstein equation".
Research on time series mining based on shape concept time warping
Institute of Scientific and Technical Information of China (English)
翁颖钧; 朱仲英
2004-01-01
Time series is an important kind of complex data, while a growing attention has been paid to mining time series knowledge recently. Typically Euclidean distance measure is used for comparing time series. However, it may be a brittle distance measure because of less robustness. Dynamic time warp is a pattern matching algorithm based on nonlinear dynamic programming technique, however it is computationally expensive and suffered from the local shape variance. A modification algorithm named by shape DTW is presented, which uses linguistic variable concept to describe the slope feather of time series. The concept tree is developed by cloud models theory which integrates randomness and probability of uncertainty, so that it makes conversion between qualitative and quantitive knowledge. Experiments about cluster analysis on the basis of this algorithm, compared with Euclidean measure, are implemented on synthetic control chart time series. The results show that this method has strong robustness to loss of feature data due to piecewise segment preprocessing. Moreover, after the construction of shape concept tree, we can discovery knowledge of time series on different time granularity.
Gesture Recognition Based on DTW and Combined Discriminative Feature Detector%基于DTW与混合判别特征检测器的手势识别
Institute of Scientific and Technical Information of China (English)
黄振翔; 彭波; 吴娟; 王儒朋
2014-01-01
在动态手势识别领域，动态时间规整(DTW)算法在消除不同时空表示模式之间的时间差异方面具有优势，但作为一种模板匹配算法，受限于样本库的容量大小并且缺乏统计模型框架训练，其识别效果和稳定性较差，尤其在大数据量、复杂手势和组合手势的情况下。针对上述不足，提出一种基于DTW和混合判别特征检测器(CFDF)的手势识别算法。利用DTW只对手势信号在时域进行规整，通过CFDF将手势特征的概率分布转换成二值的分段线性函数，根据允许的偏差范围分别做归0或归1处理后，再进行二次分类。实验结果表明，该算法通过舍弃无辨识度特征有效地降低了维度和噪声，手势平均识别率可达91.2%，比单独采用DTW的识别算法提高了6.0%。%In the dynamic gesture recognition field, the Dynamic Time Warping(DTW) algorithm, which has advantage in eliminating time differences between different space-time expression modes, is a template matching algorithm in essence, so its performance is limited by the capacity of the sample database and lacking statistical model framework to train. Its recognition result is not satisfactory and stability is poor, especially in the cases of large amount of data, complex gestures and combined gestures. In response to these deficiencies, this paper proposes a gesture recognition algorithm based on DTW and Combined Discriminative Feature Detector(CDFD). It warps gesture signals in the time domain only, uses combined discriminative feature detectors to transform probability distribution of gesture features to binary piecewise linear function and makes zero or one according to the permissible deviation ranges, finally classifies gestures. Experimental results show that this algorithm can discard non-discriminative features to reduce dimensionality and noise, and the gesture average recognition rate reaches 91.2%. Compared with individual DTW algorithm
Putting the Warp into Warp Drive
Obousy, Richard K
2008-01-01
Over the last decade, there has been a respectable level of scientific interest regarding the concept of a warp drive. This is a hypothetical propulsion device that could theoretically circumvent the traditional limitations of special relativity which restricts spacecraft to sub-light velocities. Any breakthrough in this field would revolutionize space exploration and open the doorway to interstellar travel. This article discusses a novel approach to generating the warp bubble necessary for such propulsion; the mathematical details of this theory are discussed in an article published in the Journal of the British Interpanetary Society. The theory is based on some of the exciting predictions coming out of string theory and it is the aim of this article to introduce the warp drive idea from a non-mathematical perspective that should be accessible to a wide range of readers.
ADVERSE EVENTS POST-DTAP AND DTwP VACCINATION IN THAI CHILDREN.
Fortuna, Librada; Sirivichayakul, Chukiat; Watanaveeradej, Veerachai; Soonthornworasiri, Ngamphol; Sitcharungsi, Raweerat
2015-07-01
We conducted a prospective study to compare the development of fever (axillary T ≥ 37.9 °C) within 4 hours of vaccination, determine the proportion of children who develop high fever (T ≥ 39°C) and evaluate parental days missed from work due to their children's vaccination with either the diphtheria-tetanus-whole cell pertussis (DTwP) or diphtheria-tetanus-acellular pertussis (DTaP) vaccine. The results of this study can help physicians and parents decide whether to have their child vaccinated with the DTwP or more expensive DTaP vaccine. We studied 140 healthy Thai children aged 2 months to 6 years from December 2011 to March 2012 who presented for vaccination. Parents recorded their child's temperature, local and systemic adverse reactions and missed days from work due to these adverse events on a diary card. Of the 140 participants, 72 received the DTwP vaccine and 68 received the DTaP vaccine. The median (IQR) age was 4 (2-6) months and the median weight was 7.1 (5.6-8.7) kg. Twenty children developed fever (axillary T ≥ 37.9°C) within 4 hours following vaccination, 17 (23.6%) had received the DTwP vaccine and 3 (4.4%) had received the DTaP vaccine (p = 0.040). One child (1.4%) who had received the DTwP vaccine and none who received the DTaP vaccine developed high fever (T ≥ 39°C) within 4 hours of vaccination (p = 0.329). Parents of two children who received the DTwP vaccine and one child who received the DTaP vaccine missed work following vaccination (p = 0.059). In conclusion, children who received the DTwP vaccines were more likely to have early post-vaccination fever and higher fever but there was no significant difference between the two groups in parental days lost from work.
Fault Diagnosis for Compensating Capacitors of Jointless Track Circuit Based on Dynamic Time Warping
Directory of Open Access Journals (Sweden)
Wei Dong
2014-01-01
Full Text Available Aiming at the problem of online fault diagnosis for compensating capacitors of jointless track circuit, a dynamic time warping (DTW based diagnosis method is proposed in this paper. Different from the existing related works, this method only uses the ground indoor monitoring signals of track circuit to locate the faulty compensating capacitor, not depending on the shunt current of inspection train, which is an indispensable condition for existing methods. So, it can be used for online diagnosis of compensating capacitor, which has not yet been realized by existing methods. To overcome the key problem that track circuit cannot obtain the precise position of the train, the DTW method is used for the first time in this situation to recover the function relationship between receiver’s peak voltage and shunt position. The necessity, thinking, and procedure of the method are described in detail. Besides the classical DTW based method, two improved methods for improving classification quality and reducing computation complexity are proposed. Finally, the diagnosis experiments based on the simulation model of track circuit show the effectiveness of the proposed methods.
Jiang, I G; Jiang, Ing-Guey; Binney, James
1998-01-01
N-body simulations show that when infall reorientates the outer parts of a galactic halo by several degrees per Gyr, a self-gravitating disk that is embedded in the halo develops an integral-sign warp that is comparable in amplitude to observed warps. Studies of angular-momentum acquisition suggest that the required rate of halo reorientation is realistic for galaxies like the Milky Way.
Phatak, Sayali S.; Li, Dongmei; Luka, Janos; Calderone, Richard A.
2017-01-01
Fungal infections are a global problem imposing considerable disease burden. One of the unmet needs in addressing these infections is rapid, sensitive diagnostics. A promising molecular diagnostic approach is high-resolution melt analysis (HRM). However, there has been little effort in leveraging HRM data for automated, objective identification of fungal species. The purpose of these studies was to assess the utility of distance methods developed for comparison of time series data to classify HRM curves as a means of fungal species identification. Dynamic time warping (DTW), first introduced in the context of speech recognition to identify temporal distortion of similar sounds, is an elastic distance measure that has been successfully applied to a wide range of time series data. Comparison of HRM curves of the rDNA internal transcribed spacer (ITS) region from 51 strains of 18 fungal species using DTW distances allowed accurate classification and clustering of all 51 strains. The utility of DTW distances for species identification was demonstrated by matching HRM curves from 243 previously identified clinical isolates against a database of curves from standard reference strains. The results revealed a number of prior misclassifications, discriminated species that are not resolved by routine phenotypic tests, and accurately identified all 243 test strains. In addition to DTW, several other distance functions, Edit Distance on Real sequence (EDR) and Shape-based Distance (SBD), showed promise. It is concluded that DTW-based distances provide a useful metric for the automated identification of fungi based on HRM curves of the ITS region and that this provides the foundation for a robust and automatable method applicable to the clinical setting. PMID:28264030
Immunological Links to Nonspecific Effects of DTwP and BCG Vaccines on Infant Mortality
DEFF Research Database (Denmark)
Claesson, Mogens Helweg
2011-01-01
A number of mainly observational studies suggest that many African females below the age of one year die each year from the nonspecific effects of vaccination with diphtheria-tetanus toxoids and killed (whole-cell) Bordetella pertussis (DTwP). In contrast, similar studies suggest that many African...... females and males may have their lives saved each year by the nonspecific immunological benefits of Bacillus Calmette-Guerin (BCG) vaccination. From an immunological point of view, we hypothesise that the adverse effects of DTwP vaccine may occur because of the Th2-polarising effect of the aluminium...... phosphate adjuvant in the vaccine and because intramuscular administration of the vaccine may cause chronic inflammation at the site of injection. However, the Th1-polarising effect of BCG is likely to be beneficial. Sexual dimorphism affecting immune functions and vitamin A supplementation may influence...
Immunological Links to Nonspecific Effects of DTwP and BCG Vaccines on Infant Mortality
Directory of Open Access Journals (Sweden)
Mogens Helweg Claesson
2011-01-01
Full Text Available A number of mainly observational studies suggest that many African females below the age of one year die each year from the nonspecific effects of vaccination with diphtheria-tetanus toxoids and killed (whole-cell Bordetella pertussis (DTwP. In contrast, similar studies suggest that many African females and males may have their lives saved each year by the nonspecific immunological benefits of Bacillus Calmette-Guerin (BCG vaccination. From an immunological point of view, we hypothesise that the adverse effects of DTwP vaccine may occur because of the Th2-polarising effect of the aluminium phosphate adjuvant in the vaccine and because intramuscular administration of the vaccine may cause chronic inflammation at the site of injection. However, the Th1-polarising effect of BCG is likely to be beneficial. Sexual dimorphism affecting immune functions and vitamin A supplementation may influence both the deleterious and beneficial nonspecific effects of immunisation.
Solid waste bin detection and classification using Dynamic Time Warping and MLP classifier
Energy Technology Data Exchange (ETDEWEB)
Islam, Md. Shafiqul, E-mail: shafique@eng.ukm.my [Dept. of Electrical, Electronic and Systems Engineering, Universiti Kebangsaan Malaysia, Bangi 43600, Selangore (Malaysia); Hannan, M.A., E-mail: hannan@eng.ukm.my [Dept. of Electrical, Electronic and Systems Engineering, Universiti Kebangsaan Malaysia, Bangi 43600, Selangore (Malaysia); Basri, Hassan [Dept. of Civil and Structural Engineering, Universiti Kebangsaan Malaysia, Bangi 43600, Selangore (Malaysia); Hussain, Aini; Arebey, Maher [Dept. of Electrical, Electronic and Systems Engineering, Universiti Kebangsaan Malaysia, Bangi 43600, Selangore (Malaysia)
2014-02-15
Highlights: • Solid waste bin level detection using Dynamic Time Warping (DTW). • Gabor wavelet filter is used to extract the solid waste image features. • Multi-Layer Perceptron classifier network is used for bin image classification. • The classification performance evaluated by ROC curve analysis. - Abstract: The increasing requirement for Solid Waste Management (SWM) has become a significant challenge for municipal authorities. A number of integrated systems and methods have introduced to overcome this challenge. Many researchers have aimed to develop an ideal SWM system, including approaches involving software-based routing, Geographic Information Systems (GIS), Radio-frequency Identification (RFID), or sensor intelligent bins. Image processing solutions for the Solid Waste (SW) collection have also been developed; however, during capturing the bin image, it is challenging to position the camera for getting a bin area centralized image. As yet, there is no ideal system which can correctly estimate the amount of SW. This paper briefly discusses an efficient image processing solution to overcome these problems. Dynamic Time Warping (DTW) was used for detecting and cropping the bin area and Gabor wavelet (GW) was introduced for feature extraction of the waste bin image. Image features were used to train the classifier. A Multi-Layer Perceptron (MLP) classifier was used to classify the waste bin level and estimate the amount of waste inside the bin. The area under the Receiver Operating Characteristic (ROC) curves was used to statistically evaluate classifier performance. The results of this developed system are comparable to previous image processing based system. The system demonstration using DTW with GW for feature extraction and an MLP classifier led to promising results with respect to the accuracy of waste level estimation (98.50%). The application can be used to optimize the routing of waste collection based on the estimated bin level.
Institute of Scientific and Technical Information of China (English)
王晨
2012-01-01
This paper deeply discusses ancient silk weaving techniques through researches of duplicate practice on fabric construction, loom setting process and weaving process, taking "hunting grain brocade" with a high warp density in the Eastern Zhou period unearthed in Jingan, Jiangxi, thereby revealing the key technology and scientific value of its brocade with the highest warp density so far, 240 per centimeter. It not only demonstrates the existence of brocade with a high warp density of 240 per centimeter, but also quotes that this process can produce brocade with a wide width and high warp density through duplicate practice. This research result effectively explains that exquisite techniques for weaving high-density brocade have been possessed in the Eastern Zhou period of ancient China, adding a new page for Chinese ancient brocade.%以江西靖安大墓出土的东周时期高经密织锦“狩猎纹锦”为例,通过织物结构、织机装造工艺及织造工艺等复制实践研究,展开对古代丝织技术的深度探讨,从而揭示其240根/cm迄今为止最高经密织锦的关键技术和其科学价值.通过复制实践,不仅证实了240根/cm高经密经锦的存在,还可引证该工艺可织出宽幅高经密经锦,这一研究成果有力地说明中国古代的东周时期已拥有了织造高密度织锦的精湛技术,为中国古代织锦增添新的一页.
White, Harold
2011-01-01
This paper will begin with a short review of the Alcubierre warp drive metric and describes how the phenomenon might work based on the original paper. The canonical form of the metric was developed and published in [6] which provided key insight into the field potential and boost for the field which remedied a critical paradox in the original Alcubierre concept of operations. A modified concept of operations based on the canonical form of the metric that remedies the paradox is presented and discussed. The idea of a warp drive in higher dimensional space-time (manifold) will then be briefly considered by comparing the null-like geodesics of the Alcubierre metric to the Chung-Freese metric to illustrate the mathematical role of hyperspace coordinates. The net effect of using a warp drive technology coupled with conventional propulsion systems on an exploration mission will be discussed using the nomenclature of early mission planning. Finally, an overview of the warp field interferometer test bed being implemented in the Advanced Propulsion Physics Laboratory: Eagleworks (APPL:E) at the Johnson Space Center will be detailed. While warp field mechanics has not had a Chicago Pile moment, the tools necessary to detect a modest instance of the phenomenon are near at hand.
Institute of Scientific and Technical Information of China (English)
ZHANG YanCi(张严辞); LIU XueHui(刘学慧); WU EnHua(吴恩华)
2003-01-01
In this paper a plane-based backward warping algorithm is proposed to generate novel views from multiple reference images. First, depth information is employed to reconstruct space planes from individual reference images and calculate the potential occluding relationship between these planes. Then the planes which represent each identical space plane from different reference images are compared with each other to decide the one with the best sample rate to be preserved and used in the later warping period while the other samples are abandoned. While the image of a novel view is produced, traditional methods in computer graphics, such as visibility test and clipping, are used to process the planes reconstructed. Then the planes processed are projected onto the desired image from the knowledge on which plane the desired image pixels are warped from can be acquired. Finally, pixels' depth of the desired image is calculated and then a backward warping is performed from these pixels to the reference images to obtain their colors. The storage requirement in the algorithm is small and increases slowly with the number of reference images increases. By combining the strategy of only preserving the best sample parts and the backward warping algorithm, the sample problem could be well tackled.
Cerveri, P; Forlani, C; Pedotti, A; Ferrigno, G
2003-03-01
Global polynomial (GP) methods have been widely used to correct geometric image distortion of small-size (up to 30 cm) X-ray image intensifiers (XRIIs). This work confirms that this kind of approach is suitable for 40 cm XRIIs (now increasingly used). Nonetheless, two local methods, namely 3rd-order local un-warping polynomials (LUPs) and hierarchical radial basis function (HRBF) networks are proposed as alternative solutions. Extensive experimental tests were carried out to compare these methods with classical low-order local polynomial and GP techniques, in terms of residual error (RMSE) measured at points not used for parameter estimation. Simulations showed that the LUP and HRBF methods had accuracies comparable with that attained using GP methods. In detail, the LUP method (0.353 microm) performed worse than HRBF (0.348 microm) only for small grid spacing (15 x 15 control points); the accuracy of both HRBF (0.157 microm) and LUP (0.160 microm) methods was little affected by local distortions (30 x 30 control points); weak local distortions made the GP method poorer (0.320 microm). Tests on real data showed that LUP and HRBF had accuracies comparable with that of GP for both 30 cm (GP: 0.238 microm; LUP: 0.240 microm; HRBF: 0.238 microm) and 40 cm (GP: 0.164 microm; LUP: 0.164 microm; HRBF: 0.164 microm) XRIIs. The LUP-based distortion correction was implemented in real time for image correction in digital tomography applications.
WARP Weather Information Network Server
Department of Transportation — WINS is the dissemination module of the WARP system that provides an interface to various NAS Users/systems that require weather data/products/information from WARP...
Brownian Warps for Non-Rigid Registration
DEFF Research Database (Denmark)
Nielsen, Mads; Johansen, Peter; Jackson, Andrew D.;
2008-01-01
prior, we formulate a Partial Differential Equation for obtaining the maximally likely warp given matching constraints derived from the images. We solve for the free boundary conditions, and the bias toward smaller areas in the finite domain setting. Furthermore, we demonstrate the technique on 2D...
Kuijken, K.; García, I.
2000-01-01
Abstract: This review addresses recent developments in the field of disk galaxy warps. Both results from a new HI survey of edgeon disk galaxies, and of simulations of the interaction between a disk+halo and an orbiting satelite, will be discussed.
Kuijken, K; Kuijken, Konrad; Garcia, Inigo
2000-01-01
This review addresses recent developments in the field of disk galaxy warps. Both results from a new HI survey of edgeon disk galaxies, and of simulations of the interaction between a disk+halo and an orbiting satelite, will be discussed.
Zhang, Dongliang
2014-08-05
The quality of migration images depends on the accuracy of the velocity model. For large velocity errors, the migration image is strongly distorted, which unflattens events in the common image gathers and consequently leads to a blurring in the stacked migration image. To mitigate this problem, we propose dynamic image warping to flatten the common image gathers before stacking and to enhance the signal-to-noise ratio of the migration image. Numerical tests on the Marmousi model and GOM data show that image warping of the prestack images followed by stacking leads to much better resolved reflectors than the original migration image. The problem, however, is that the reflector locations have increased uncertainty because the wrong velocity model is still used.
Chinese Calligraphy Word Spotting Using Elastic HOG Feature and Derivative Dynamic Time Warping
Institute of Scientific and Technical Information of China (English)
Yong Xia; Zhi-Bo Yang; Kuan-Quan Wang
2014-01-01
Chinese calligraphy is a very special style of handwriting and direct character recognition is very difficult. Content-based keyword spotting is more feasible than recognition-based retrieval for calligraphy document. In this paper, we propose a novel Elastic Histogram of Oriented Gradient ( EHOG) descriptor for calligraphy word spotting. The presented feature is a modification of Histogram of Oriented Gradient (HOG), widely used in human detection. In our approach, the input word image is partitioned into non-uniform rectangular cells according to the calligraphy character pixel intensity, and then in each cell a histogram of orientation is accumulated dynamically. Moreover, we adopt Derivative Dynamic Time Warping ( DDTW) for image feature matching, which achieves good performance in gesture recognition. Experiments demonstrate a very significant improvement when comparing our proposed feature with previously developed ones, and also show DDTW produces superior alignments between two calligraphy character feature series than DTW.
Modified DTW for a quantitative estimation of the similarity between rainfall time series
Djallel Dilmi, Mohamed; Barthès, Laurent; Mallet, Cécile; Chazottes, Aymeric
2017-04-01
interpretation of this inter-correlation is not straightforward. We propose here to use an improvement of the Euclidian distance which integrates the global complexity of the rainfall series. The Dynamic Time Wrapping (DTW) used in speech recognition allows matching two time series instantly different and provide the most probable time lag. However, the original formulation of the DTW suffers from some limitations. In particular, it is not adequate to the rain intermittency. In this study we present an adaptation of the DTW for the analysis of rainfall time series : we used time series from the "Météo France" rain gauge network observed between January 1st, 2007 and December 31st, 2015 on 25 stations located in the Île de France area. Then we analyze the results (eg. The distance, the relationship between the time lag detected by our methods and others measured parameters like speed and direction of the wind…) to show the ability of the proposed similarity to provide usefull information on the rain structure. The possibility of using this measure of similarity to define a quality indicator of a sensor integrated into an observation network is also envisaged.
Quantum effects in warp drives
Directory of Open Access Journals (Sweden)
Finazzi Stefano
2013-09-01
Full Text Available Warp drives are interesting configurations that, at least theoretically, provide a way to travel at superluminal speed. Unfortunately, several issues seem to forbid their realization. First, a huge amount of exotic matter is required to build them. Second, the presence of quantum fields propagating in superluminal warp-drive geometries makes them semiclassically unstable. Indeed, a Hawking-like high-temperature flux of particles is generated inside the warp-drive bubble, which causes an exponential growth of the energy density measured at the front wall of the bubble by freely falling observers. Moreover, superluminal warp drives remain unstable even if the Lorentz symmetry is broken by the introduction of regulating higher order terms in the Lagrangian of the quantum field. If the dispersion relation of the quantum field is subluminal, a black-hole laser phenomenon yields an exponential amplification of the emitted flux. If it is superluminal, infrared effects cause a linear growth of this flux.
Time Warp Operating System (TWOS)
Bellenot, Steven F.
1993-01-01
Designed to support parallel discrete-event simulation, TWOS is complete implementation of Time Warp mechanism - distributed protocol for virtual time synchronization based on process rollback and message annihilation.
Warped branches of flux compactifications
Lim, Yen-Kheng
2012-01-01
We consider Freund-Rubin-type compactifications which are described by (p+q)-dimensional Einstein gravity with a positive cosmological constant and a q-form flux. Using perturbative expansions of Kinoshita's ansatz for warped dS_pxS^q and AdS_pxS^q spacetimes, we obtain analytical solutions describing the warped branches and their respective phase spaces. These equations are given by inhomogeneous Gegenbauer differential equations which can be solved by the Green's function method. The requirement that the Green's functions are regular provides constraints which determine the structure of the phase space of the warped branches. We apply the perturbation results to calculate the thermodynamic variables for the warped dS_pxS^q branch. In particular, the first law of thermodynamics can be reproduced using this method.
Time Warp Operating System (TWOS)
Bellenot, Steven F.
1993-01-01
Designed to support parallel discrete-event simulation, TWOS is complete implementation of Time Warp mechanism - distributed protocol for virtual time synchronization based on process rollback and message annihilation.
Conformal boundaries of warped products
DEFF Research Database (Denmark)
Kokkendorff, Simon Lyngby
2006-01-01
In this note we prove a result on how to determine the conformal boundary of a type of warped product of two length spaces in terms of the individual conformal boundaries. In the situation, that we treat, the warping and conformal distortion functions are functions of distance to a base point....... The result is applied to produce examples of CAT(0)-spaces, where the conformal and ideal boundaries differ in interesting ways....
Dynamics of warped accretion discs
Tremaine, Scott; Davis, Shane W.
2013-01-01
Accretion discs are present around both stellar-mass black holes in X-ray binaries and supermassive black holes in active galactic nuclei. A wide variety of circumstantial evidence implies that many of these discs are warped. The standard Bardeen--Petterson model attributes the shape of the warp to the competition between Lense--Thirring torque from the central black hole and viscous angular-momentum transport within the disc. We show that this description is incomplete, and that torques from...
Warped Geometry of Brane Worlds
Felder, G; Kofman, L A; Felder, Gary; Frolov, Andrei; Kofman, Lev
2002-01-01
We study the dynamical equations for a warp factor and a bulk scalar in 5d brane world scenarios. These equations are similar to those for the time dependence of the scale factor and a scalar field in 4d cosmology, but with the sign of the scalar field potential reversed. Based on this analogy, we introduce two novel methods for studying the warped geometry. First, we construct the full phase portraits of the warp factor/scalar system for several examples of the bulk potential. This allows us to view the global properties of the warped geometry. For flat branes, the phase portrait is two dimensional. Moving along typical phase trajectories, the warp factor is initially increasing and finally decreasing. All trajectories have timelike gradient-dominated singularities at one or both of their ends, which are reachable in a finite distance and must be screened by the branes. For curved branes, the phase portrait is three dimensional. However, as the warp factor increases the phase trajectories tend towards the tw...
Warped Supersymmetric Grand Unification
Goldberger, W D; Smith, D R; Goldberger, Walter D.; Nomura, Yasunori; Smith, David R.
2003-01-01
We construct a realistic model of grand unification in AdS_5 truncated by branes, in which the unified gauge symmetry is broken by boundary conditions and the electroweak scale is generated by the AdS warp factor. We show that the model preserves the successful gauge coupling unification of the 4D MSSM at leading-logarithmic level. Kaluza-Klein towers, including those of XY gauge and colored Higgs multiplets, appear at the TeV scale, while the extra dimension provides natural mechanisms for doublet-triplet splitting and proton decay suppression. In one possible scenario supersymmetry is strongly broken on the TeV brane, in which case the lightest SU(3)_C x SU(2)_L x U(1)_Y gauginos are Dirac fermions, with universal masses at the weak scale, and the mass of the lightest XY gaugino is pushed well below that of the lowest gauge boson KK mode, improving the prospects for its production at the LHC. The bulk Lagrangian possesses a symmetry that we call GUT parity. If GUT parity is exact, the lightest GUT particle,...
Environmental Dependence of Warps in Spiral Galaxies
Ann, Hong Bae; Bae, Hyun Jeong
2016-12-01
We determined the warp parameters of 192 warped galaxies which are selected from 340 edge-on galaxies using color images as well as r-band isophotal maps. We derive the local background density (Σ_{n}) to examine the dependence of the warp amplitudes on the galaxy environment. We find a clear trend that strongly warped galaxies are likely to be found in high density regions where tidal interactions are supposed to be frequent. However, the correlation between α_{w} and Σ_{n} is too weak for weakly warped galaxies (α_{w} decisive role in the formation of weak warps.}
Gesture Acceleration Signals Recognition Based on Dynamic Time Warping%基于动态时间规整的手势加速度信号识别
Institute of Scientific and Technical Information of China (English)
荆雷; 马文君; 常丹华
2012-01-01
A dynamic time warping algorithm of gesture recognition was used to improve the performance of dynamic gesture recognition based on accelerometer. The similarity between test template and reference template is calculated by dynamic time warping method(DTW) ,and the results of recognition are got from these similarities. To confirm our algorithm, a wireless gesture acceleration measurement system is proposed and measurements gesture information on 41 volunteers is collected. The results show that the average gesture rate is above 97%. Compared with the algorithm of hidden Markov model(HMM) ,the DTW algorithm is more precise in recognition accuracy.%为了提高基于加速度传感器的动态手势识别算法的性能,本文采用了动态时间规整(DTW)识别算法.通过该算法计算测试模板和参考模板的相似度,从而得出识别结果.为了验证该方法,建立了一套手势加速度无线采集系统,并采集了41个志愿者的手势信息.实验结果表明,该方法手势平均识别率在97％以上.与HMM识别算法相比,DTW识别算法在识别的准确率上比HMM识别算法更具优势.
Wireless Augmented Reality Prototype (WARP)
Devereaux, A. S.
1999-01-01
Initiated in January, 1997, under NASA's Office of Life and Microgravity Sciences and Applications, the Wireless Augmented Reality Prototype (WARP) is a means to leverage recent advances in communications, displays, imaging sensors, biosensors, voice recognition and microelectronics to develop a hands-free, tetherless system capable of real-time personal display and control of computer system resources. Using WARP, an astronaut may efficiently operate and monitor any computer-controllable activity inside or outside the vehicle or station. The WARP concept is a lightweight, unobtrusive heads-up display with a wireless wearable control unit. Connectivity to the external system is achieved through a high-rate radio link from the WARP personal unit to a base station unit installed into any system PC. The radio link has been specially engineered to operate within the high- interference, high-multipath environment of a space shuttle or space station module. Through this virtual terminal, the astronaut will be able to view and manipulate imagery, text or video, using voice commands to control the terminal operations. WARP's hands-free access to computer-based instruction texts, diagrams and checklists replaces juggling manuals and clipboards, and tetherless computer system access allows free motion throughout a cabin while monitoring and operating equipment.
Barth, Jens; Oberndorfer, Cäcilia; Pasluosta, Cristian; Schülein, Samuel; Gassner, Heiko; Reinfelder, Samuel; Kugler, Patrick; Schuldhaus, Dominik; Winkler, Jürgen; Klucken, Jochen; Eskofier, Björn M
2015-03-17
Changes in gait patterns provide important information about individuals' health. To perform sensor based gait analysis, it is crucial to develop methodologies to automatically segment single strides from continuous movement sequences. In this study we developed an algorithm based on time-invariant template matching to isolate strides from inertial sensor signals. Shoe-mounted gyroscopes and accelerometers were used to record gait data from 40 elderly controls, 15 patients with Parkinson's disease and 15 geriatric patients. Each stride was manually labeled from a straight 40 m walk test and from a video monitored free walk sequence. A multi-dimensional subsequence Dynamic Time Warping (msDTW) approach was used to search for patterns matching a pre-defined stride template constructed from 25 elderly controls. F-measure of 98% (recall 98%, precision 98%) for 40 m walk tests and of 97% (recall 97%, precision 97%) for free walk tests were obtained for the three groups. Compared to conventional peak detection methods up to 15% F-measure improvement was shown. The msDTW proved to be robust for segmenting strides from both standardized gait tests and free walks. This approach may serve as a platform for individualized stride segmentation during activities of daily living.
Directory of Open Access Journals (Sweden)
Jens Barth
2015-03-01
Full Text Available Changes in gait patterns provide important information about individuals’ health. To perform sensor based gait analysis, it is crucial to develop methodologies to automatically segment single strides from continuous movement sequences. In this study we developed an algorithm based on time-invariant template matching to isolate strides from inertial sensor signals. Shoe-mounted gyroscopes and accelerometers were used to record gait data from 40 elderly controls, 15 patients with Parkinson’s disease and 15 geriatric patients. Each stride was manually labeled from a straight 40 m walk test and from a video monitored free walk sequence. A multi-dimensional subsequence Dynamic Time Warping (msDTW approach was used to search for patterns matching a pre-defined stride template constructed from 25 elderly controls. F-measure of 98% (recall 98%, precision 98% for 40 m walk tests and of 97% (recall 97%, precision 97% for free walk tests were obtained for the three groups. Compared to conventional peak detection methods up to 15% F-measure improvement was shown. The msDTW proved to be robust for segmenting strides from both standardized gait tests and free walks. This approach may serve as a platform for individualized stride segmentation during activities of daily living.
Warped products and conformal boundaries of CAT(0)-Spaces
DEFF Research Database (Denmark)
Buckley, S.M.; Kokkendorff, Simon Lyngby
2008-01-01
We discuss the conformal boundary of a warped product of two length spaces and provide a method to calculate this in terms of the individual conformal boundaries. This technique is then applied to produce CAT(0)-spaces with complicated conformal boundaries. Finally, we prove that the conformal...
DigiWarp: a method for deformable mouse atlas warping to surface topographic data
Energy Technology Data Exchange (ETDEWEB)
Joshi, Anand A; Shattuck, David W; Toga, Arthur W [Laboratory of Neuro Imaging, UCLA School of Medicine, Los Angeles, CA 90095 (United States); Chaudhari, Abhijit J [Department of Radiology, UC Davis School of Medicine, Sacramento, CA 95817 (United States); Li Changqing; Cherry, Simon R [Department of Biomedical Engineering, University of California-Davis, Davis, CA 95616 (United States); Dutta, Joyita; Leahy, Richard M, E-mail: anand.joshi@loni.ucla.ed, E-mail: leahy@sipi.usc.ed [Signal and Image Processing Institute, University of Southern California, Los Angeles, CA 90089 (United States)
2010-10-21
For pre-clinical bioluminescence or fluorescence optical tomography, the animal's surface topography and internal anatomy need to be estimated for improving the quantitative accuracy of reconstructed images. The animal's surface profile can be measured by all-optical systems, but estimation of the internal anatomy using optical techniques is non-trivial. A 3D anatomical mouse atlas may be warped to the estimated surface. However, fitting an atlas to surface topography data is challenging because of variations in the posture and morphology of imaged mice. In addition, acquisition of partial data (for example, from limited views or with limited sampling) can make the warping problem ill-conditioned. Here, we present a method for fitting a deformable mouse atlas to surface topographic range data acquired by an optical system. As an initialization procedure, we match the posture of the atlas to the posture of the mouse being imaged using landmark constraints. The asymmetric L{sup 2} pseudo-distance between the atlas surface and the mouse surface is then minimized in order to register two data sets. A Laplacian prior is used to ensure smoothness of the surface warping field. Once the atlas surface is normalized to match the range data, the internal anatomy is transformed using elastic energy minimization. We present results from performance evaluation studies of our method where we have measured the volumetric overlap between the internal organs delineated directly from MRI or CT and those estimated by our proposed warping scheme. Computed Dice coefficients indicate excellent overlap in the brain and the heart, with fair agreement in the kidneys and the bladder.
Warped product submanifolds of Lorentzian paracosymplectic manifolds
Perkta\\cs, Selcen Yüksel; Kele\\cs, Sad\\ik
2011-01-01
In this paper we study the warped product submanifolds of a Lorentzian paracosymplectic manifold and obtain some nonexistence results. We show that a warped product semi-invariant submanifold in the form {$M=M_{T}\\times_{f}M_{\\bot}$} of Lorentzian paracosymplectic manifold such that the characteristic vector field is normal to $M$ is an usual Riemannian product manifold where totally geodesic and totally umbilical submanifolds of warped product are invariant and anti-invariant, respectively. We prove that the distributions involved in the definition of a warped product semi-invariant submanifold are always integrable. A necessary and sufficient condition for a semi-invariant submanifold of a Lorentzian paracosymplectic manifold to be warped product semi-invariant submanifold is obtained. We also investigate the existence and nonexistence of warped product semi-slant and warped product anti-slant submanifolds in a Lorentzian paracosymplectic manifold.
Directory of Open Access Journals (Sweden)
VIMALA C.
2015-05-01
Full Text Available In recent years, speech technology has become a vital part of our daily lives. Various techniques have been proposed for developing Automatic Speech Recognition (ASR system and have achieved great success in many applications. Among them, Template Matching techniques like Dynamic Time Warping (DTW, Statistical Pattern Matching techniques such as Hidden Markov Model (HMM and Gaussian Mixture Models (GMM, Machine Learning techniques such as Neural Networks (NN, Support Vector Machine (SVM, and Decision Trees (DT are most popular. The main objective of this paper is to design and develop a speaker-independent isolated speech recognition system for Tamil language using the above speech recognition techniques. The background of ASR system, the steps involved in ASR, merits and demerits of the conventional and machine learning algorithms and the observations made based on the experiments are presented in this paper. For the above developed system, highest word recognition accuracy is achieved with HMM technique. It offered 100% accuracy during training process and 97.92% for testing process.
Stepinski, T. F.; Netzel, P.; Jasiewicz, J.
2014-12-01
We have developed a novel method for classification and search of climate over the global land surface excluding Antarctica. Our method classifies climate on the basis of the outcome of time series segmentation and clustering. We use WorldClim 30 arc sec. (approx. 1 km) resolution grid data which is based on 50 years of climatic observations. Each cell in a grid is assigned a 12 month series consisting of 50-years monthly averages of mean, maximum, and minimum temperatures as well as the total precipitation. The presented method introduces several innovations with comparison to existing data-driven methods of world climate classifications. First, it uses only climatic rather than bioclimatic data. Second, it employs object-oriented methodology - the grid is first segmented before climatic segments are classified. Third, and most importantly, the similarity between climates in two given cells is performed using the dynamic time warping (DTW) measure instead of the Euclidean distance. The DTW is known to be superior to Euclidean distance for time series, but has not been utilized before in classification of global climate. To account for computational expense of DTW we use highly efficient GeoPAT software (http://sil.uc.edu/gitlist/) that, in the first step, segments the grid into local regions of uniform climate. In the second step, the segments are classified. We also introduce a climate search - a GeoWeb-based method for interactive presentation of global climate information in the form of query-and-retrieval. A user selects a geographical location and the system returns a global map indicating level of similarity between local climates and a climate in the selected location. The results of the search for location: "University of Cincinnati, Main Campus" are presented on attached map. The results of the search for location: "University of Cincinnati, Main Campus" are presented on the map. We have compared the results of our method to Koeppen classification scheme
Warping the Weak Gravity Conjecture
Directory of Open Access Journals (Sweden)
Karta Kooner
2016-08-01
Full Text Available The Weak Gravity Conjecture, if valid, rules out simple models of Natural Inflation by restricting their axion decay constant to be sub-Planckian. We revisit stringy attempts to realise Natural Inflation, with a single open string axionic inflaton from a probe D-brane in a warped throat. We show that warped geometries can allow the requisite super-Planckian axion decay constant to be achieved, within the supergravity approximation and consistently with the Weak Gravity Conjecture. Preliminary estimates of the brane backreaction suggest that the probe approximation may be under control. However, there is a tension between large axion decay constant and high string scale, where the requisite high string scale is difficult to achieve in all attempts to realise large field inflation using perturbative string theory. We comment on the Generalized Weak Gravity Conjecture in the light of our results.
The Warp computer: Architecture, implementation, and performance
Energy Technology Data Exchange (ETDEWEB)
Annaratone, M.; Arnould, E.; Gross, T.; Kung, H.T.; Lam, M.; Menzilcioglu, O.; Webb, J.A.
1987-12-01
The Warp machine is a systolic array computer of linearly connected cells, each of which is a programmable processor capable of performing 10 million floating-point operations per second (10 MFLOPS). A typical Warp array includes ten cells, thus having a peak computation rate of 100 MFLOPS. The Warp array can be extended to include more cells to accommodate applications capable of using the increased computational bandwidth. Warp is integrated as an attached processor into a Unix host system. Programs for Warp are written in a high-level language supported by an optimizing complier. This paper describes the architecture, implementation, and performance of the Warp machine. Each major architectural decision is discussed and evaluated with system, software, and application considerations. The programming model and tools developed for the machine are also described. The paper concludes with performance data for a large number of applications.
Audio Effects Based on Biorthogonal Time-Varying Frequency Warping
Directory of Open Access Journals (Sweden)
Cavaliere Sergio
2001-01-01
Full Text Available We illustrate the mathematical background and musical use of a class of audio effects based on frequency warping. These effects alter the frequency content of a signal via spectral mapping. They can be implemented in dispersive tapped delay lines based on a chain of all-pass filters. In a homogeneous line with first-order all-pass sections, the signal formed by the output samples at a given time is related to the input via the Laguerre transform. However, most musical signals require a time-varying frequency modification in order to be properly processed. Vibrato in musical instruments or voice intonation in the case of vocal sounds may be modeled as small and slow pitch variations. Simulation of these effects requires techniques for time-varying pitch and/or brightness modification that are very useful for sound processing. The basis for time-varying frequency warping is a time-varying version of the Laguerre transformation. The corresponding implementation structure is obtained as a dispersive tapped delay line, where each of the frequency dependent delay element has its own phase response. Thus, time-varying warping results in a space-varying, inhomogeneous, propagation structure. We show that time-varying frequency warping is associated to an expansion over biorthogonal sets generalizing the discrete Laguerre basis. Slow time-varying characteristics lead to slowly varying parameter sequences. The corresponding sound transformation does not suffer from discontinuities typical of delay lines based on unit delays.
The Current Status of the WARP Experiment
Szelc, A. M.; Benetti, P.; Calligarich, E.; Calaprice, F.; Cambiaghi, M.; Carbonara, F.; Cavanna, F.; Cocco, A. G.; Dipompeo, F.; Ferrari, N.; Fiorillo, G.; Galbiati, C.; Grandi, L.; Mangano, G.; Montanari, C.; Palamara, O.; Pandola, L.; Rappoldi, A.; Raselli, G. L.; Roncadelli, M.; Rossella, M.; Rubbia, C.; Santorelli, R.; Vignoli, C.; Zhao, Y.
2006-07-01
The WARP detector is a new idea in Dark Matter detection using liquid noble gases, specifically argon. We believe that argon is the medium best suited to detect nuclear recoils coming from interactions with the so called WIMPs (Weakly Interacting Massive Particles). The detection technique, using two different discrimination methods, is capable of an identification power as high as one event in 108. During the second half of the year 2006 the next, 100 liter, detector will be constructed with an active veto shield to further suppress the background, while currently a 2.3 liter prototype, installed in the Gran Sasso Laboratory (Italy), has been taking data since May 2004. The small version of the detector is able to not only provide insight on the operation of a two-phase liquid argon chamber but is also able to provide physics results competitive with the current leading edge experiments.
Black holes and warped spacetime
Energy Technology Data Exchange (ETDEWEB)
Kaufmann, W.J. III
1979-01-01
Black holes (BHs) and their warping effect on spacetime are described, beginning with a discussion on stellar evolution that includes white dwarfs, supernovas and neutron stars. The structure of static, rotating, and electrically charged BHs are considered, as well as the general theory of relativity, quantum mechanics, the Einstein-Rosen bridge, and wormholes in spacetime. Attention is also given to gravitational lenses, various space geometries, quasars, Seyfert galaxies, supermassive black holes, the evaporation and particle emission of BHs, and primordial BHs, including their temperature and lifetime.
Warped Circumbinary Disks in Active Galactic Nuclei
Hayasaki, Kimitake; Okazaki, Atsuo T; Jung, Taehyun; Zhao, Guangyao; Naito, Tsuguya
2014-01-01
We study a warping instability of a geometrically thin, non-self-gravitating disk surrounding binary supermassive black holes on a circular orbit. Such a circumbinary disk is subject to not only tidal torques due to the binary gravitational potential but also radiative torques due to radiation emitted from an accretion disk around each black hole. We find that a circumbinary disk initially aligned with the binary orbital plane is unstable to radiation-driven warping beyond the marginally stable warping radius, which is sensitive to both the ratio of vertical to horizontal shear viscosities and the mass-to-energy conversion efficiency. As expected, the tidal torques give no contribution to the growth of warping modes but tend to align the circumbinary disk with the orbital plane. Since the tidal torques can suppress the warping modes in the inner part of circumbinary disk, the circumbinary disk starts to be warped at radii larger than the marginally stable warping radius. If the warping radius is of the order ...
Seamless warping of diffusion tensor fields
DEFF Research Database (Denmark)
Xu, Dongrong; Hao, Xuejun; Bansal, Ravi;
2008-01-01
To warp diffusion tensor fields accurately, tensors must be reoriented in the space to which the tensors are warped based on both the local deformation field and the orientation of the underlying fibers in the original image. Existing algorithms for warping tensors typically use forward mapping...... deformations in an attempt to ensure that the local deformations in the warped image remains true to the orientation of the underlying fibers; forward mapping, however, can also create "seams" or gaps and consequently artifacts in the warped image by failing to define accurately the voxels in the template...... space where the magnitude of the deformation is large (e.g., |Jacobian| > 1). Backward mapping, in contrast, defines voxels in the template space by mapping them back to locations in the original imaging space. Backward mapping allows every voxel in the template space to be defined without the creation...
The geometry of warped product singularities
Stoica, Ovidiu Cristinel
In this article, the degenerate warped products of singular semi-Riemannian manifolds are studied. They were used recently by the author to handle singularities occurring in General Relativity, in black holes and at the big-bang. One main result presented here is that a degenerate warped product of semi-regular semi-Riemannian manifolds with the warping function satisfying a certain condition is a semi-regular semi-Riemannian manifold. The connection and the Riemann curvature of the warped product are expressed in terms of those of the factor manifolds. Examples of singular semi-Riemannian manifolds which are semi-regular are constructed as warped products. Applications include cosmological models and black holes solutions with semi-regular singularities. Such singularities are compatible with a certain reformulation of the Einstein equation, which in addition holds at semi-regular singularities too.
Geodesic congruences in warped spacetimes
Ghosh, Suman; Kar, Sayan
2010-01-01
In this article, we explore the kinematics of timelike geodesic congruences in warped five dimensional bulk spacetimes, with and without thick or thin branes. We begin our investigations with the simplest case, namely geodesic flows in the Randall--Sundrum AdS (Anti de Sitter) geometry without and with branes. Analytical expressions for the expansion scalar are obtained and the effect of including one or more thin branes (i.e. a background which is a slice of AdS spacetime) on its evolution, is pointed out. Subsequently, we move on to studying such congruences in more general warped bulk geometries with a cosmological thick brane and a time-dependent extra dimensional scale. Using the analytical expressions for the velocity field components, we interpret the expansion, shear and rotation (ESR) along the flows. The evolution of a cross-sectional area orthogonal to the congruence, as seen from a local observer's point of view, is also shown graphically. Finally, the Raychaudhuri and geodesic equations in the ba...
Design of Warped Stretch Transform
Mahjoubfar, Ata; Chen, Claire Lifan; Jalali, Bahram
2015-11-01
Time stretch dispersive Fourier transform enables real-time spectroscopy at the repetition rate of million scans per second. High-speed real-time instruments ranging from analog-to-digital converters to cameras and single-shot rare-phenomena capture equipment with record performance have been empowered by it. Its warped stretch variant, realized with nonlinear group delay dispersion, offers variable-rate spectral domain sampling, as well as the ability to engineer the time-bandwidth product of the signal’s envelope to match that of the data acquisition systems. To be able to reconstruct the signal with low loss, the spectrotemporal distribution of the signal spectrum needs to be sparse. Here, for the first time, we show how to design the kernel of the transform and specifically, the nonlinear group delay profile dictated by the signal sparsity. Such a kernel leads to smart stretching with nonuniform spectral resolution, having direct utility in improvement of data acquisition rate, real-time data compression, and enhancement of ultrafast data capture accuracy. We also discuss the application of warped stretch transform in spectrotemporal analysis of continuous-time signals.
Efficient Similarity Retrieval in Music Databases
DEFF Research Database (Denmark)
Ruxanda, Maria Magdalena; Jensen, Christian Søndergaard
2006-01-01
object is modeled as a time sequence of high-dimensional feature vectors, and dynamic time warping (DTW) is used as the similarity measure. To accomplish this, the paper extends techniques for time-series-length reduction and lower bounding of DTW distance to the multi-dimensional case. Further...
The warp drive and antigravity
Ellis, H G
2004-01-01
The warp drive envisioned by Alcubierre that can move a spaceship faster than light can, with modification, levitate it as if it were lighter than light, even allow it to go below a black hole's horizon and return unscathed. Wormhole-like versions of the author's `drainhole' (1973) might provide the drive, in the form of a by-pass of the spaceship composed of a multitude of tiny topological tunnels. The by-pass would divert the gravitational `ether' into a sink covering part of the spaceship's hull, connected by the tunnels to a source covering the remainder of the hull, to produce an ether flow like that of a river that disappears underground only to spring forth at a point downstream. This diversion would effectively shield the spaceship from external gravity.
Planetary plains: subsidence and warping
Kochemasov, G.
A common feature of all celestial bodies is their tectonic dichotomy best studied, naturally, at Earth [1]. Here there is an opposition of the eastern continental hemisphere and the western oceanic one. The first one is uplifted and cracked, the second one subsided, squeezed and warped. The next excellent example of dichotomy is at Mars where the subsided northern hemisphere is opposed by the highly uplifted southern one. The enigmatic two-face Iapetus now with help of Cassini SC presents a more clear picture: the leading dark hemisphere is opposed by the trailing light one. The light hemisphere is built mainly of water ice, the dark one of some more dense material. Bean-shaped asteroids with one convex and another concave hemispheres are best exemplified by Ida. Examples of dichotomic asteroids, satellites, planets and stars could be extended. Ubiquity of this phenomenon was expressed as the 1st theorem of the planetary wave tectonics [2 & others]: "Celestial bodies are dichotomic". A reason of this phenomenon is in action of inertia-gravity waves occurring in any celestial body because of its movement in non-round but elliptical (parabolic) orbit with periodically changing accelerations. The inertia-gravity standing waves warp rotating bodies (but all bodies rotate !) in 4 ortho- and diagonal interfering directions and in several harmonic wave-lengths. The fundamental wave1 produces ubiquitous tectonic dichotomy (2πR-structure): an opposition of two hemispheres with different planetary radii. To keep angular momenta of two hemispheres equal (otherwise a body will fall apart) the lower subsiding one is constructed of denser material than the higher one. Normally in terrestrial planets lowlands are filled with dense basalts, highlands are built by lighter lithologies. A subsidence means diminishing radius, otherwise, the larger surface must be fit into a smaller space. It is possible only if an original infilling is warped. At Earth cosmic altimetry shows complex
Warped functional analysis of variance.
Gervini, Daniel; Carter, Patrick A
2014-09-01
This article presents an Analysis of Variance model for functional data that explicitly incorporates phase variability through a time-warping component, allowing for a unified approach to estimation and inference in presence of amplitude and time variability. The focus is on single-random-factor models but the approach can be easily generalized to more complex ANOVA models. The behavior of the estimators is studied by simulation, and an application to the analysis of growth curves of flour beetles is presented. Although the model assumes a smooth latent process behind the observed trajectories, smootheness of the observed data is not required; the method can be applied to irregular time grids, which are common in longitudinal studies.
Seamless warping of diffusion tensor fields
DEFF Research Database (Denmark)
Xu, Dongrong; Hao, Xuejun; Bansal, Ravi
2008-01-01
To warp diffusion tensor fields accurately, tensors must be reoriented in the space to which the tensors are warped based on both the local deformation field and the orientation of the underlying fibers in the original image. Existing algorithms for warping tensors typically use forward mapping...... of seams, including voxels in which the deformation is extensive. Backward mapping, however, cannot reorient tensors in the template space because information about the directional orientation of fiber tracts is contained in the original, unwarped imaging space only, and backward mapping alone cannot...... transfer that information to the template space. To combine the advantages of forward and backward mapping, we propose a novel method for the spatial normalization of diffusion tensor (DT) fields that uses a bijection (a bidirectional mapping with one-to-one correspondences between image spaces) to warp DT...
Hydrodynamics in Class B Warped Spacetimes
Carot, J
2005-01-01
We discuss certain general features of type B warped spacetimes which have important consequences on the material content they may admit and its associated dynamics. We show that, for Warped B spacetimes, if shear and anisotropy are nonvanishing, they have to be proportional. We also study some of the physics related to the warping factor and of the underlying decomposable metric. Finally we explore the only possible cases compatible with a type B Warped geometry which satisfy the dominant energy conditions. As an example of the above mentioned consequences we consider a radiating fluid and two non-spherically symmetric metrics which depend upon an arbitrary parameter, such that if the parameter vanishes the spherical symmetry is recovered.
Galactic Warps Formed through Cosmic Infall
Shen, J.; Sellwood, J. A.
2004-12-01
The extended HI disks of many edge-on spiral galaxies appear noticeably warped away from the inner disk with an ``integral sign'' shape. At least half, perhaps all, of spiral galaxies are warped. The origin and maintenance of warps are still not well understood. We use fully self-consistent N-body simulations to study the effect of cosmic infall on an isolated disk galaxy, which we find to be a promising way of making warps. The amplitude and morphology of warps formed in an idealized experiment to test this scenario resemble observations closely. The agreement with Briggs (1990)'s rules is also very encouraging: the inner disk tilts remarkably rigidly, indicating the strong cohesion due to the self-gravity; the line of nodes (LON) inside R26.5 ˜ 4.5 Rd is straight; and the LON beyond R26.5 always forms a loosely-wound leading spiral. We show that the leading spiral arises from the torque from the misaligned inner disk. In this scenario the damping of a warp by the halo is weak, because the free precession rate of the inner disk is slow and the inner halo generally remains aligned with the inner disk. Thus warps formed this way can persist for a relatively long time (a few Gyrs), by which time another infall event can be expected. We also point out the spirality of the LON of warps in this idealized model should twist from leading to trailing at very large radii, such feature may be observable in future HI surveys.
Broken discs: warp propagation in accretion discs
Nixon, Chris; King, Andrew
2012-01-01
We simulate the viscous evolution of an accretion disc around a spinning black hole. In general any such disc is misaligned, and warped by the Lense-Thirring effect. Unlike previous studies we use effective viscosities constrained to be consistent with the internal fluid dynamics of the disc. We find that nonlinear fluid effects, which reduce the effective viscosities in warped regions, can promote the breaking of the disc into two distinct planes. This occurs when the Shakura & Sunyaev dimen...
New Lower Bounds for Warp Drive Energy
Gauthier, C.; Gravel, P.; Melanson, J.
The introduction of the warp drive metric by Alcubierre1 has aroused great interest over the past few years. Using an uncertainty-type principle, Ford and Pfenning2 proved that the warp drive transport of a spaceship in a regular bubble having a radius of 100 m is unrealistic. However, Van Den Broeck3 has shown that the situation largely improves when one uses a warp drive bubble with a small surface area and large spatial volume. Putting aside many physics problems related to the realization of the warp drive concept, we show in this paper4 how to modify Van Den Broeck's idea to improve his results. We find new lower bounds for the warp drive energy by working on parameters whose latitude has never been considered before. We also consider micro warp drive bubbles which can be treated as physical entities of their own and could possibly be used to transmit information faster than the speed of light. The conditions prevailing just after the Big Bang allow the spontaneous formation of such micro bubbles which could still be present in our period of time.
Matching colonic polyps using correlation optimized warping
Wang, Shijun; Yao, Jianhua; Petrick, Nicholas; Summers, Ronald M.
2010-03-01
Computed tomographic colonography (CTC) combined with a computer aided detection system has the potential for improving colonic polyp detection and increasing the use of CTC for colon cancer screening. In the clinical use of CTC, a true colonic polyp will be confirmed with high confidence if a radiologist can find it on both the supine and prone scans. To assist radiologists in CTC reading, we propose a new method for matching polyp findings on the supine and prone scans. The method performs a colon registration using four automatically identified anatomical salient points and correlation optimized warping (COW) of colon centerline features. We first exclude false positive detections using prediction information from a support vector machine (SVM) classifier committee to reduce initial false positive pairs. Then each remaining CAD detection is mapped to the other scan using COW technique applied to the distance along the centerline in each colon. In the last step, a new SVM classifier is applied to the candidate pair dataset to find true polyp pairs between supine and prone scans. Experimental results show that our method can improve the sensitivity to 0.87 at 4 false positive pairs per patient compared with 0.72 for a competing method that uses the normalized distance along the colon centerline (p<0.01).
Combes, F.
Polar ring galaxies, where matter is in equilibrium in perpendicular orbits around spiral galaxies, are ideal objects to probe the 3D shapes of dark matter halos. The conditions to constrain the halos are that the perpendicular system does not strongly perturb the host galaxy, or that it is possible to derive back its initial shape, knowing the formation scenario of the polar ring. The formation mechanisms are reviewed: mergers, tidal accretion, or gas accretion from cosmic filaments. The Tully-Fisher diagram for polar rings reveals that the velocity in the polar plane is higher than in the host plane, which can only be explained if the dark matter is oblate and flattened along the polar plane. Only a few individual systems have been studied in details, and 3D shapes of their haloes determined by several methods. The high frequency of warps could be explained by spontaneous bending instability, if the disks are sufficiently self-gravitating, which can put constraints on the dark matter flattening.
Combes, F
2005-01-01
Polar ring galaxies, where matter is in equilibrium in perpendicular orbits around spiral galaxies, are ideal objects to probe the 3D shapes of dark matter halos. The conditions to constrain the halos are that the perpendicular system does not strongly perturb the host galaxy, or that it is possible to derive back its initial shape, knowing the formation scenario of the polar ring. The formation mechanisms are reviewed: mergers, tidal accretion, or gas accretion from cosmic filaments. The Tully-Fisher diagram for polar rings reveals that the velocity in the polar plane is higher than in the host plane, which can only be explained if the dark matter is oblate and flattened along the polar plane. Only a few individual systems have been studied in details, and 3D shapes of their haloes determined by several methods. The high frequency of warps could be explained by spontaneous bending instability, if the disks are sufficiently self-gravitating, which can put constraints on the dark matter flattening.
Diphoton portal to warped gravity
Falkowski, Adam; Kamenik, Jernej F.
2016-07-01
The diphoton excess around mX=750 GeV observed by ATLAS and CMS can be interpreted as coming from a massive spin-2 excitation. We explore this possibility in the context of warped five-dimensional models with the Standard Model (SM) fields propagating in the bulk of the extra dimension. The 750 GeV resonance is identified with the first Kaluza-Klein (KK) excitation of the five-dimensional graviton that is parametrically lighter than KK resonances of SM fields. Our setup makes it possible to realize nonuniversal couplings of the spin-2 resonance to matter, and thus to explain nonobservation of the 750 GeV resonance in leptonic channels. Phenomenological predictions of the model depend on the localization of fields in the extra dimension. If, as required by naturalness arguments, the zero modes of the Higgs and top fields are localized near the IR brane, one expects large branching fractions to t t ¯, h h , W+W- and Z Z final states. Decays to Z γ can also be observable when the KK graviton couplings to the SM gauge fields are nonuniversal.
Semiclassical instability of dynamical warp drives
Finazzi, Stefano; Barceló, Carlos
2009-01-01
Warp drives are very interesting configurations in General Relativity: At least theoretically, they provide a way to travel at superluminal speeds, albeit at the cost of requiring exotic matter to exist as solutions of Einstein's equations. However, even if one succeeded in providing the necessary exotic matter to build them, it would still be necessary to check whether they would survive to the switching on of quantum effects. Semiclassical corrections to warp-drive geometries have been analyzed only for eternal warp-drive bubbles traveling at fixed superluminal speeds. Here, we investigate the more realistic case in which a superluminal warp drive is created out of an initially flat spacetime. First of all we analyze the causal structure of eternal and dynamical warp-drive spacetimes. Then we pass to the analysis of the renormalized stress-energy tensor (RSET) of a quantum field in these geometries. While the behavior of the RSET in these geometries has close similarities to that in the geometries associate...
Density of States for Warped Energy Bands
Mecholsky, Nicholas A.; Resca, Lorenzo; Pegg, Ian L.; Fornari, Marco
2016-02-01
Warping of energy bands can affect the density of states (DOS) in ways that can be large or subtle. Despite their potential for significant practical impacts on materials properties, these effects have not been rigorously demonstrated previously. Here we rectify this using an angular effective mass formalism that we have developed. To clarify the often confusing terminology in this field, “band warping” is precisely defined as pertaining to any multivariate energy function E(k) that does not admit a second-order differential at an isolated critical point in k-space, which we clearly distinguish from band non-parabolicity. We further describe band “corrugation” as a qualitative form of band warping that increasingly deviates from being twice differentiable at an isolated critical point. These features affect the density-of-states and other parameters ascribed to band warping in various ways. We demonstrate these effects, providing explicit calculations of DOS and their effective masses for warped energy dispersions originally derived by Kittel and others. Other physical and mathematical examples are provided to demonstrate fundamental distinctions that must be drawn between DOS contributions that originate from band warping and contributions that derive from band non-parabolicity. For some non-degenerate bands in thermoelectric materials, this may have profound consequences of practical interest.
Bouncing Brane Cosmologies from Warped String Compactifications
Kachru, S
2003-01-01
We study the cosmology induced on a brane probing a warped throat region in a Calabi-Yau compactification of type IIB string theory. For the case of a BPS D3-brane probing the Klebanov-Strassler warped deformed conifold, the cosmology described by a suitable brane observer is a bouncing, spatially flat Friedmann-Robertson-Walker universe with time-varying Newton's constant, which passes smoothly from a contracting to an expanding phase. In the Klebanov-Tseytlin approximation to the Klebanov-Strassler solution the cosmology would end with a big crunch singularity. In this sense, the warped deformed conifold provides a string theory resolution of a spacelike singularity in the brane cosmology. The four-dimensional effective action appropriate for a brane observer is a simple scalar-tensor theory of gravity. In this description of the physics, a bounce is possible because the relevant energy-momentum tensor can classically violate the null energy condition.
Dark Energy Generated by Warped Cosmic Strings
Slagter, Reinoud Jan
2014-01-01
If we live on the weak brane in a warped 5D bulk spacetime, gravitational waves and brane fluctuations can be generated by a part of the 5D Weyl tensor and carries information of the gravitational field outside the brane. We consider the U(1) self-gravitating scalar-gauge field on the warped spacetime without bulk matter. It turns out that "branons" can be formed dynamically, due to the modified energy-momentum tensor components of the cosmic string. It turns out that the parameter $\\alpha$, i.e., the gauge-to-scalar mass, changes from a value $>1$ to a value $<1$ and the solution approaches a static global string by shedding off wave energy. It is the time-dependent part of the warp factor which triggers this extraordinary behavior.
Inflation on the resolved warped deformed conifold
Buchel, A
2006-01-01
Braneworld inflation on the resolved warped deformed conifold is represented by the dynamics of a D3-brane probe with the world volume of a brane spanning the large dimensions of the observable Universe. This model was recently proposed as a string theory candidate for slow-roll inflationary cosmology in hep-th/0511254. During inflation, the scalar curvature of the Universe is determined by the Hubble scale. We argue that taking into account the curvature of the inflationary Universe renders dynamics of the D3-brane fast-roll deep inside the warped throat.
Origin of the warped heliospheric current sheet
Energy Technology Data Exchange (ETDEWEB)
Wilcox, J.M.; Hoeksema, J.T.; Scherrer, P.H.
1980-08-01
The warped heliospheric current sheet for early 1976 is calculated from the observed photospheric magnetic field by a potential field method. Comparisons with measurements of the interplanetary magnetic field polarity for early 1976 obtained at several locations in the heliosphere by Helios 1, Helios 2, Pioneer 11, and at the earth show a rather detailed agreement between the computed current sheet and the observations. It appears that the large-scale structure of the warped heliospheric current sheet is determined by the structure of the photospheric magnetic field and that ballerina skirt effects may add small-scale ripples.
Origin of the warped heliospheric current sheet
Wilcox, J. M.; Hoeksema, J. T.; Scherrer, P. H.
1980-08-01
The warped heliospheric current sheet for early 1976 is calculated from the observed photospheric magnetic field by a potential field method. Comparisons with measurements of the interplanetary magnetic field polarity for early 1976 obtained at several locations in the heliosphere by Helios 1, Helios 2, Pioneer 11, and at the earth show a rather detailed agreement between the computed current sheet and the observations. It appears that the large-scale structure of the warped heliospheric current sheet is determined by the structure of the photospheric magnetic field and that 'ballerina skirt' effects may add small scale ripples.
Warped K\\"ahler potentials and fluxes
Martucci, Luca
2016-01-01
The four-dimensional effective theory for type IIB warped flux compactifications proposed in [1] is completed by taking into account the backreaction of the K\\"ahler moduli on the three-form fluxes. The only required modification consists in a flux-dependent contribution to the chiral fields parametrising the K\\"ahler moduli. The resulting supersymmetric effective theory satisfies the no-scale condition and consistently combines previous partial results present in the literature. Similar results hold for M-theory warped compactifications on Calabi-Yau fourfolds, whose effective field theory and K\\"ahler potential are also discussed.
Cardone, D.; Pinti, P.; Di Donato, L.; Merla, A.
2017-06-01
A relevant issue for processing biomedical thermal imaging data is the availability of tools for objective and quantitative comparison of images across different conditions or subjects. To this goal, a solution can be offered by projecting the thermal distribution data onto a fictitious template to obtain a common reference for comparison across cases or subjects. In this preliminary study, we tested the feasibility of applying a warping procedure on infrared thermal images. Fifteen thermal images of checkerboard were recorded at three different distances and five different angles in order to evaluate which factor mostly influences the warping accuracy. The accuracy of three different warping transformation models (local weighted mean (LWM), polynomial, affine) was tested by comparing the positioning error between users' selected fiduciary points on each thermal image and their corresponding reference position assigned on the template image. Fifteen users, divided into three groups upon on their experience in thermal imaging processing, participated in this study in order to evaluate the effect of experience in applying a warping procedure to the analysis of thermal infrared images. The most relevant factor influencing the positioning and thermal errors is the acquisition distance, while the users' level of experience and the inclination angle do not seem to play the same importance. Comparing the three transformations, the LWM seems to be the best in terms of minimizing the two categories of errors. This preliminary work helps to understand the limits and the possibilities of applying warping techniques for objective, quantitative and automatic thermal image comparisons.
An arc-length warping algorithm for gesture recognition using quaternion representation.
Cifuentes, Jenny; Pham, Minh Tu; Moreau, Richard; Prieto, Flavio; Boulanger, Pierre
2013-01-01
This paper presents a new algorithm, called Dynamic Arc-Length Warping algorithm (DALW) for hand gesture recognition based on the orientation data. In this algorithm, after calculating the quaternion for each orientation measurement, we use DALW algorithm to obtain a similarity measure between different trajectories. We present the benefits of using quaternion alongside the implementation of Dynamic Arc Length Warping to present an optimized tool for gesture recognition.We show the advantages of this approach compared with other techniques. This tool can be used to distinguish similar and different gestures. An experimental validation is carried out to classify a series of simple human gestures.
Tilt, Warp, and Simultaneous Precessions in Disks
Montgomery, M M
2012-01-01
Warps are suspected in disks around massive compact objects. However, the proposed warping source -- non-axisymmetric radiation pressure -- does not apply to white dwarfs. In this letter we report the first Smoothed Particle Hydrodynamic simulations of accretion disks in SU UMa-type systems that naturally tilt, warp, and simultaneously precess in the prograde and retrograde directions using white dwarf V344 Lyrae in the Kepler field as our model. After ~79 days in V344 Lyrae, the disk angular momentum L_d becomes misaligned to the orbital angular momentum L_o. As the gas stream remains normal to L_o, hydrodynamics (e.g., the lift force) is a likely source to disk tilt. In addition to tilt, the outer disk annuli cyclically change shape from circular to highly eccentric due to tidal torques by the secondary star. The effect of simultaneous prograde and retrograde precession is a warp of the colder, denser midplane as seen along the disk rim. The simulated rate of apsidal advance to nodal regression per orbit ne...
Entanglement Entropy in Warped Conformal Field Theories
Castro, A.; Hofman, D.M.; Iqbal, N.
We present a detailed discussion of entanglement entropy in (1+1)-dimensional Warped Conformal Field Theories (WCFTs). We implement the Rindler method to evaluate entanglement and Renyi entropies for a single interval and along the way we interpret our results in terms of twist field correlation
Radiation-Driven Warping. 2; Nonisothermal Disks
Maloney, Philip R.; Begelman, Mitchell C.; Nowak, Michael A.
1998-01-01
Recent work by Pringle and by Maloney, Begelman, & Pringle has shown that geometrically thin, optically thick, accretion disks are unstable to warping driven by radiation torque from the central source. This work was confined to isothermal (i.e., surface density Sigma varies as R(sup -3/2) disks. In this paper we generalize the study of radiation-driven warping to include general power-law surface density distributions, Sigma varies as R(sup -delta).We consider the range from Delta = 3/2 (the isothermal case) to Delta = -3/2, which corresponds to a radiation-pressure-supported disk; this spans the range of surface density distributions likely to be found in real astrophysical disks. In all cases there are an infinite number of zero-crossing solutions (i.e., solutions that cross the equator), which are the physically relevant modes if the outer boundary of the disk is required to lie in a specified plane. However, unlike the isothermal disk, which is the degenerate case, the frequency eigenvalues for Delta does not equal 3/2 are all distinct. In all cases the location of the zero moves outward from the steady state (pure precession) value with increasing growth rate; thus, there is a critical minimum size for unstable disks. Modes with zeros at smaller radii are damped. The critical radius and the steady state precession rate depend only weakly on Delta. An additional analytic solution has been found for Delta = 1. The case Delta = 1 divides the solutions into two qualitatively different regimes. For Delta greater than or equal to 1, the fastest growing modes have maximum warp amplitude, close to the disk outer edge, and the ratio of Beta(sub max) to the warp amplitude at the disk inner edge, Beta(sub o), is much greater than 1. For Delta less than 1, Beta(sub max/Beta(sub o) approximately equals 1, and the warp maximum steadily approaches the origin as Delta decreases. This implies that nonlinear effects must be important if the warp extends to the disk inner edge
Entanglement entropy in warped conformal field theories
Energy Technology Data Exchange (ETDEWEB)
Castro, Alejandra; Hofman, Diego M.; Iqbal, Nabil [Institute for Theoretical Physics, University of Amsterdam,Science Park 904, Postbus 94485, 1090 GL Amsterdam (Netherlands)
2016-02-04
We present a detailed discussion of entanglement entropy in (1+1)-dimensional Warped Conformal Field Theories (WCFTs). We implement the Rindler method to evaluate entanglement and Renyi entropies for a single interval and along the way we interpret our results in terms of twist field correlation functions. Holographically a WCFT can be described in terms of Lower Spin Gravity, a SL(2,ℝ)×U(1) Chern-Simons theory in three dimensions. We show how to obtain the universal field theory results for entanglement in a WCFT via holography. For the geometrical description of the theory we introduce the concept of geodesic and massive point particles in the warped geometry associated to Lower Spin Gravity. In the Chern-Simons description we evaluate the appropriate Wilson line that captures the dynamics of a massive particle.
Brane modeling in warped extra-dimension
Ahmed, Aqeel
2012-01-01
Five-dimensional scenarios with infinitesimally thin branes replaced by appropriate configurations of a scalar field were considered. A possibility of periodic extra dimension was discussed in the presence on non-minimal scalar-gravity coupling and a generalized Gibbons-Kallosh-Linde sum rule was found. In order to avoid constraints imposed by periodicity, a non-compact spacial extra dimension was introduced. A five dimensional model with warped geometry and two thin branes mimicked by a scalar profile was constructed and discussed. In the thin brane limit the model corresponds to a set-up with two positive-tension branes. The presence of two branes allows to address the issue of the hierarchy problem which could be solved by the standard warping of the four dimensional metric. Stability of the background solution was discussed and verified in the presence of the most general perturbations of the metric and the scalar field.
Entanglement Entropy in Warped Conformal Field Theories
Castro, Alejandra; Iqbal, Nabil
2015-01-01
We present a detailed discussion of entanglement entropy in (1+1)-dimensional Warped Conformal Field Theories (WCFTs). We implement the Rindler method to evaluate entanglement and Renyi entropies for a single interval and along the way we interpret our results in terms of twist field correlation functions. Holographically a WCFT can be described in terms of Lower Spin Gravity, a SL(2,R)xU(1) Chern-Simons theory in three dimensions. We show how to obtain the universal field theory results for entanglement in a WCFT via holography. For the geometrical description of the theory we introduce the concept of geodesic and massive point particles in the warped geometry associated to Lower Spin Gravity. In the Chern-Simons description we evaluate the appropriate Wilson line that captures the dynamics of a massive particle.
Wormholes, warp drives and energy conditions
2017-01-01
Top researchers in the field of gravitation present the state-of-the-art topics outlined in this book, ranging from the stability of rotating wormholes solutions supported by ghost scalar fields, modified gravity applied to wormholes, the study of novel semi-classical and nonlinear energy conditions, to the applications of quantum effects and the superluminal version of the warp drive in modified spacetime. Based on Einstein's field equations, this cutting-edge research area explores the more far-fetched theoretical outcomes of General Relativity and relates them to quantum field theory. This includes quantum energy inequalities, flux energy conditions, and wormhole curvature, and sheds light on not just the theoretical physics but also on the possible applications to warp drives and time travel. This book extensively explores the physical properties and characteristics of these 'exotic spacetimes,' describing in detail the general relativistic geometries that generate closed timelike curves.
Fermions in a warped resolved conifold
Dantas, D M; Almeida, C A S
2013-01-01
We investigated the localization of the spinorial field in a braneworld built as a warped product between a 3-brane and a 2-cycle of the resolved conifold. This scenario provides a geometric flow that controls the singularity at the origin and changes the properties of the fermion in this background. Furthermore, due the cylindrical symmetry according to the 3-brane and a smoothed warp factor, this geometry can be regarded as a near brane correction of the string-like branes. This geometry allows a normalizable and well-defined massless mode whose decay and value on the brane depend on the resolution parameter. For the Kaluza-Klein modes, resolution parameter also controls the height of the barrier of the volcano potential.
Graviton modes in multiply warped geometry
Energy Technology Data Exchange (ETDEWEB)
Arun, Mathew Thomas, E-mail: thomas.mathewarun@gmail.com [Department of Physics and Astrophysics, University of Delhi, Delhi 110007 (India); Choudhury, Debajyoti, E-mail: debajyoti.choudhury@gmail.com [Department of Physics and Astrophysics, University of Delhi, Delhi 110007 (India); Das, Ashmita, E-mail: ashmita.phy@gmail.com [Department of Theoretical Physics, Indian Association for the Cultivation of Sciences, 2A& B R.S.C. Mullick Road, Kolkata 700 032 (India); SenGupta, Soumitra, E-mail: soumitraiacs@gmail.com [Department of Theoretical Physics, Indian Association for the Cultivation of Sciences, 2A& B R.S.C. Mullick Road, Kolkata 700 032 (India)
2015-06-30
The negative results in the search for Kaluza–Klein graviton modes at the LHC, when confronted with the discovery of the Higgs, have been construed to have severely limited the efficacy of the Randall–Sundrum model as an explanation of the hierarchy problem. We show, though, that the presence of multiple warping offers a natural resolution of this conundrum through modifications in both the graviton spectrum and their couplings to the Standard Model fields.
Flavor universal resonances and warped gravity
Agashe, Kaustubh; Du, Peizhi; Hong, Sungwoo; Sundrum, Raman
2017-01-01
Warped higher-dimensional compactifications with "bulk" standard model, or their AdS/CFT dual as the purely 4D scenario of Higgs compositeness and partial compositeness, offer an elegant approach to resolving the electroweak hierarchy problem as well as the origins of flavor structure. However, low-energy electroweak/flavor/CP constraints and the absence of non-standard physics at LHC Run 1 suggest that a "little hierarchy problem" remains, and that the new physics underlying naturalness may lie out of LHC reach. Assuming this to be the case, we show that there is a simple and natural extension of the minimal warped model in the Randall-Sundrum framework, in which matter, gauge and gravitational fields propagate modestly different degrees into the IR of the warped dimension, resulting in rich and striking consequences for the LHC (and beyond). The LHC-accessible part of the new physics is AdS/CFT dual to the mechanism of "vectorlike confinement", with TeV-scale Kaluza-Klein excitations of the gauge and gravitational fields dual to spin-0,1,2 composites. Unlike the minimal warped model, these low-lying excitations have predominantly flavor-blind and flavor/CP-safe interactions with the standard model. Remarkably, this scenario also predicts small deviations from flavor-blindness originating from virtual effects of Higgs/top compositeness at ˜ O(10) TeV, with subdominant resonance decays into Higgs/top-rich final states, giving the LHC an early "preview" of the nature of the resolution of the hierarchy problem. Discoveries of this type at LHC Run 2 would thereby anticipate (and set a target for) even more explicit explorations of Higgs compositeness at a 100 TeV collider, or for next-generation flavor tests.
Kaluza-Klein relics from warped reheating
Berndsen, Aaron; Stoica, Horace
2007-01-01
It has been suggested that after brane-antibrane inflation in a Klebanov-Strassler (KS) warped throat, metastable Kaluza-Klein (KK) excitations can be formed due to nearly-conserved angular momenta along isometric directions in the throat. If sufficiently long-lived, these relics could conflict with big bang nucleosynthesis or baryogenesis by dominating the energy density of the universe. We make a detailed estimate of the decay rate of such relics using the low energy effective action of type IIB string theory compactified on the throat geometry, with attention to powers of the warp factor. We find that it is necessary to turn on SUSY-breaking deformations of the KS background in order to ensure that the most dangerous relics will decay. The decay rate is found to be much larger than the naive guess based on the dimension of the operators which break the angular isometries of the throat. For an inflationary warp factor of order w ~ 10^{-4}, we obtain the bound M_{3/2} > 10^8 GeV on the scale of SUSY breaking...
Warped Brane Worlds in Six Dimensional Supergravity
Aghababaie, Y; Cline, J M; Firouzjahi, H; Parameswaran, S L; Quevedo, Fernando; Tasinato, G; Zavala, I
2003-01-01
We present warped compactification solutions of six-dimensional supergravity, which are generalizations of the Randall-Sundrum warped brane world to codimension two and to a supersymmetric context. In these solutions the dilaton varies over the extra dimensions, and this makes the electroweak hierarchy only power-law sensitive to the proper radius of the extra dimensions (as opposed to being exponentially sensitive as in the RS model). Warping changes the phenomenology of these models because the Kaluza-Klein gap can be much larger than the internal space's inverse proper radius. We provide examples both for Romans' nonchiral supergravity and Salam-Sezgin chiral supergravity, and in both cases the solutions break all of the supersymmetries of the models. We interpret the solution as describing the fields sourced by a 3-brane and a boundary 4-brane (Romans' supergravity) or by one or two 3-branes (Salam-Sezgin supergravity), and we identify the topological constraints which are required by this interpretation....
Flavor Universal Resonances and Warped Gravity
Agashe, Kaustubh; Hong, Sungwoo; Sundrum, Raman
2016-01-01
Warped higher-dimensional compactifications with "bulk" standard model, or their AdS/CFT dual as the purely 4D scenario of Higgs compositeness and partial compositeness, offer an elegant approach to resolving the electroweak hierarchy problem as well as the origins of flavor structure. However, low-energy electroweak/flavor/CP constraints and the absence of non-standard physics at LHC Run 1 suggest that a "little hierarchy problem" remains, and that the new physics underlying naturalness may lie out of LHC reach. Assuming this to be the case, we show that there is a simple and natural extension of the minimal warped model in the Randall-Sundrum framework, in which matter, gauge and gravitational fields propagate modestly different degrees into the IR of the warped dimension, resulting in rich and striking consequences for the LHC (and beyond). The LHC-accessible part of the new physics is AdS/CFT dual to the mechanism of "vectorlike confinement", with TeV-scale Kaluza-Klein excitations of the gauge and gravit...
Realization of an Automated Vertical Warp Stop Motion Positioning
Directory of Open Access Journals (Sweden)
Frederik Cloppenburg
2015-02-01
Full Text Available The tension in the warp yarns is a critical variable in the weaving process. If the warp tension is too high or too low the weaving process will be interrupted. A parameter that directly affects the warp tension is the vertical warp stop motion position. The position of the warp stop motion must be set for every produced new article. The setting procedure is performed completely manual. In this paper we present a mechatronic modification of an air jet-weaving machine to adjust the vertical warp stop motion position with the help of actuators. The parameters for the automated movement are determined and an open loop control, which uses a PLC, is proposed.
Interactions Between Massive Dark Halos And Warped Disks
Kuijken, Konrad
1996-01-01
The normal mode theory for warping of galaxy disks, in which disks are assumed to be tilted with respect to the equator of a massive, flattened dark halo, assumes a rigid, fixed halo. However, consideration of the back-reaction by a misaligned disk on a massive particle halo shows there to be strong coupling leading to efficient damping (or in some circumstances excitation) of the misalignment, and hence the warp. We therefore discuss possible alternative explanations of the warp phenomenon, ...
Constraining the age of the NGC 4565 HI Disk Warp: Determining the Origin of Gas Warps
Radburn-Smith, David J; Streich, David; Bell, Eric F; Dalcanton, Julianne J; Dolphin, Andrew E; Stilp, Adrienne M; Monachesi, Antonela; Holwerda, Benne W; Bailin, Jeremy
2013-01-01
We have mapped the distribution of young and old stars in the gaseous HI warp of NGC 4565. We find a clear correlation of young stars (1 Gyr), which places an upper limit on the age of the structure. The formation rate of the young stars, which increased ~300 Myr ago relative to the surrounding regions, is (6.3 +2.5/-1.5) x 10^-5 M_sol/yr/kpc^2. This implies a ~60+/-20 Gyr depletion time of the HI warp, similar to the timescales calculated for the outer HI disks of nearby spiral galaxies. While some stars associated with the warp fall into the asymptotic giant branch (AGB) region of the color magnitude diagram, where stars could be as old as 1 Gyr, further investigation suggests that they may be interlopers rather than real AGB stars. We discuss the implications of these age constraints for the formation of HI warps, and the gas fueling of disk galaxies.
Focusing of branes in warped backgrounds
Kar, S
2006-01-01
Branes are embedded surfaces in a given background (bulk) spacetime. Assuming a warped bulk, we investigate, in analogy with the case for geodesics, the notion of {\\em focusing} of families of such embedded, extremal 3--branes in a five dimensional background . The essential tool behind our analysis, is the well-known generalised Raychaudhuri equations for surface congruences. In particular, we find explicit solutions of these equations, which seem to show that families of 3--branes can focus along lower dimensional submanifolds depending on where the initial expansions are specified. We conclude with comments on the results obtained and possibilities about future work along similar lines.
Characterization of multiaxial warp knit composites
Dexter, H. Benson; Hasko, Gregory H.; Cano, Roberto J.
1991-01-01
The objectives were to characterize the mechanical behavior and damage tolerance of two multiaxial warp knit fabrics to determine the acceptability of these fabrics for high performance composite applications. The tests performed included compression, tension, open hole compression, compression after impact and compression-compression fatigue. Tests were performed on as-fabricated fabrics and on multi-layer fabrics that were stitched together with either carbon or Kevlar stitching yarn. Results of processing studies for vacuum impregnation with Hercules 3501-6 epoxy resin and pressure impregnation with Dow Tactix 138/H41 epoxy resin and British Petroleum BP E905L epoxy resin are presented.
Variations on the Warped Deformed Conifold
Gubser, S S; Klebanov, I R; Gubser, Steven S.; Herzog, Christopher P.; Klebanov, Igor R.
2004-01-01
The warped deformed conifold background of type IIB theory is dual to the cascading $SU(M(p+1))\\times SU(Mp)$ gauge theory. We show that this background realizes the (super-)Goldstone mechanism where the U(1) baryon number symmetry is broken by expectation values of baryonic operators. The resulting massless pseudo-scalar and scalar glueballs are identified in the supergravity spectrum. A D-string is then dual to a global string in the gauge theory. Upon compactification, the Goldstone mechanism turns into the Higgs mechanism, and the global strings turn into ANO strings.
Enhancing face recognition by image warping
García Bueno, Jorge
2009-01-01
This project has been developed as an improvement which could be added to the actual computer vision algorithms. It is based on the original idea proposed and published by Rob Jenkins and Mike Burton about the power of the face averages in arti cial recognition. The present project aims to create a new automated procedure applied for face recognition working with average images. Up to now, this algorithm has been used manually. With this study, the averaging and warping process will be done b...
Relaxation of Warped Disks: the Case of Pure Hydrodynamics
Sorathia, Kareem A; Hawley, John F
2013-01-01
Orbiting disks may exhibit bends due to a misalignment between the angular momentum of the inner and outer regions of the disk. We begin a systematic simulational inquiry into the physics of warped disks with the simplest case: the relaxation of an unforced warp under pure fluid dynamics, i.e. with no internal stresses other than Reynolds stress. We focus on the nonlinear regime in which the bend rate is large compared to the disk aspect ratio. When warps are nonlinear, strong radial pressure gradients drive transonic radial motions along the disk's top and bottom surfaces that efficiently mix angular momentum. The resulting nonlinear decay rate of the warp increases with the warp rate and the warp width, but, at least in the parameter regime studied here, is independent of the sound speed. The characteristic magnitude of the associated angular momentum fluxes likewise increases with both the local warp rate and the radial range over which the warp extends; it also increases with increasing sound speed, but m...
Warped electroweak breaking without custodial symmetry
Cabrer, Joan A.; von Gersdorff, Gero; Quirós, Mariano
2011-03-01
We propose an alternative to the introduction of an extra gauge (custodial) symmetry to suppress the contribution of KK modes to the T parameter in warped theories of electroweak breaking. The mechanism is based on a general class of warped 5D metrics and a Higgs propagating in the bulk. The metrics are nearly AdS in the UV region but depart from AdS in the IR region, towards where KK fluctuations are mainly localized, and have a singularity outside the slice between the UV and IR branes. This gravitational background is generated by a bulk stabilizing scalar field which triggers a natural solution to the hierarchy problem. Depending on the model parameters, gauge-boson KK modes can be consistent with present bounds on EWPT for mKK≳1 TeV at 95% CL. The model contains a light Higgs mode which unitarizes the four-dimensional theory. The reduction in the precision observables can be traced back to a large wave function renormalization for this mode.
Warped Electroweak Breaking Without Custodial Symmetry
Cabrer, Joan A; Quiros, Mariano
2010-01-01
We propose an alternative to the introduction of an extra gauge (custodial) symmetry to suppress the contribution of KK modes to the T parameter in warped theories of electroweak breaking. The mechanism is based on a general class of warped 5D metrics and a Higgs propagating in the bulk. The metrics are nearly AdS in the UV region but depart from AdS in the IR region, towards where KK fluctuations are mainly localized, and have a singularity outside the slice between the UV and IR branes. This gravitational background is generated by a bulk stabilizing scalar field which triggers a natural solution to the hierarchy problem. Depending on the model parameters, gauge-boson KK modes can be consistent with present bounds on EWPT for m > 1 TeV at 95% CL. The model contains a light Higgs mode which unitarizes the four-dimensional theory. The reduction in the precision observables can be traced back to a large wave function renormalization for this mode.
NASA's Wireless Augmented Reality Prototype (WARP)
Agan, Martin; Voisinet, Leeann; Devereaux, Ann
1998-01-01
The objective of Wireless Augmented Reality Prototype (WARP) effort is to develop and integrate advanced technologies for real-time personal display of information relevant to the health and safety of space station/shuttle personnel. The WARP effort will develop and demonstrate technologies that will ultimately be incorporated into operational Space Station systems and that have potential earth applications such as aircraft pilot alertness monitoring and in various medical and consumer environments where augmented reality is required. To this end a two phase effort will be undertaken to rapidly develop a prototype (Phase I) and an advanced prototype (Phase II) to demonstrate the following key technology features that could be applied to astronaut internal vehicle activity (IVA) and potentially external vehicle activity (EVA) as well: 1) mobile visualization, and 2) distributed information system access. Specifically, Phase I will integrate a low power, miniature wireless communication link and a commercial biosensor with a head mounted display. The Phase I design will emphasize the development of a relatively small, lightweight, and unobtrusive body worn prototype system. Phase II will put increased effort on miniaturization, power consumption reduction, increased throughput, higher resolution, and ``wire removal'' of the subsystems developed in Phase I.
Adaptive space warping to enhance passive haptics in an arthroscopy surgical simulator.
Spillmann, Jonas; Tuchschmid, Stefan; Harders, Matthias
2013-04-01
Passive haptics, also known as tactile augmentation, denotes the use of a physical counterpart to a virtual environment to provide tactile feedback. Employing passive haptics can result in more realistic touch sensations than those from active force feedback, especially for rigid contacts. However, changes in the virtual environment would necessitate modifications of the physical counterparts. In recent work space warping has been proposed as one solution to overcome this limitation. In this technique virtual space is distorted such that a variety of virtual models can be mapped onto one single physical object. In this paper, we propose as an extension adaptive space warping; we show how this technique can be employed in a mixed-reality surgical training simulator in order to map different virtual patients onto one physical anatomical model. We developed methods to warp different organ geometries onto one physical mock-up, to handle different mechanical behaviors of the virtual patients, and to allow interactive modifications of the virtual structures, while the physical counterparts remain unchanged. Various practical examples underline the wide applicability of our approach. To the best of our knowledge this is the first practical usage of such a technique in the specific context of interactive medical training.
Lee, Kyeong-sang; Choi, Sungwon; Seo, Minji; Lee, Chang suk; Seong, Noh-hun; Han, Kyung-Soo
2016-10-01
Snow cover is biggest single component of cryosphere. The Snow is covering the ground in the Northern Hemisphere approximately 50% in winter season and is one of climate factors that affects Earth's energy budget because it has higher reflectance than other land types. Also, snow cover has an important role about hydrological modeling and water resource management. For this reason, accurate detection of snow cover acts as an essential element for regional water resource management. Snow cover detection using satellite-based data have some advantages such as obtaining wide spatial range data and time-series observations periodically. In the case of snow cover detection using satellite data, the discrimination of snow and cloud is very important. Typically, Misclassified cloud and snow pixel can lead directly to error factor for retrieval of satellite-based surface products. However, classification of snow and cloud is difficult because cloud and snow have similar optical characteristics and are composed of water or ice. But cloud and snow has different reflectance in 1.5 1.7 μm wavelength because cloud has lower grain size and moisture content than snow. So, cloud and snow shows difference reflectance patterns change according to wavelength. Therefore, in this study, we perform algorithm for classifying snow cover and cloud with satellite-based data using Dynamic Time Warping (DTW) method which is one of commonly used pattern analysis such as speech and fingerprint recognitions and reflectance spectral library of snow and cloud. Reflectance spectral library is constructed in advance using MOD21km (MODIS Level1 swath 1km) data that their reflectance is six channels including 3 (0.466μm), 4 (0.554μm), 1 (0.647μm), 2 (0.857μm), 26 (1.382μm) and 6 (1.629μm). We validate our result using MODIS RGB image and MOD10 L2 swath (MODIS swath snow cover product). And we use PA (Producer's Accuracy), UA (User's Accuracy) and CI (Comparison Index) as validation criteria
Directory of Open Access Journals (Sweden)
Christopher D Buckley
Full Text Available The warp ikat method of making decorated textiles is one of the most geographically widespread in southeast Asia, being used by Austronesian peoples in Indonesia, Malaysia and the Philippines, and Daic peoples on the Asian mainland. In this study a dataset consisting of the decorative characters of 36 of these warp ikat weaving traditions is investigated using Bayesian and Neighbornet techniques, and the results are used to construct a phylogenetic tree and taxonomy for warp ikat weaving in southeast Asia. The results and analysis show that these diverse traditions have a common ancestor amongst neolithic cultures the Asian mainland, and parallels exist between the patterns of textile weaving descent and linguistic phylogeny for the Austronesian group. Ancestral state analysis is used to reconstruct some of the features of the ancestral weaving tradition. The widely held theory that weaving motifs originated in the late Bronze Age Dong-Son culture is shown to be inconsistent with the data.
Buckley, Christopher D
2012-01-01
The warp ikat method of making decorated textiles is one of the most geographically widespread in southeast Asia, being used by Austronesian peoples in Indonesia, Malaysia and the Philippines, and Daic peoples on the Asian mainland. In this study a dataset consisting of the decorative characters of 36 of these warp ikat weaving traditions is investigated using Bayesian and Neighbornet techniques, and the results are used to construct a phylogenetic tree and taxonomy for warp ikat weaving in southeast Asia. The results and analysis show that these diverse traditions have a common ancestor amongst neolithic cultures the Asian mainland, and parallels exist between the patterns of textile weaving descent and linguistic phylogeny for the Austronesian group. Ancestral state analysis is used to reconstruct some of the features of the ancestral weaving tradition. The widely held theory that weaving motifs originated in the late Bronze Age Dong-Son culture is shown to be inconsistent with the data.
Analysis of Similarity of DNA Sequences Based on Dynamic Time Warping Distabce%基于DTW距离的DNA序列相似性分析
Institute of Scientific and Technical Information of China (English)
李梅; 白凤兰
2009-01-01
在DNA序列相似性的研究中,通常采用的动态规划算法对空位罚分函数缺乏理论依据而带有主观性,从而取得不同的结果,本文提出了一种基于DTW(Dynamic Time Warping,动态时间弯曲)距离的DNA序列相似性度量方法可以解决这一问题.通过DNA序列的图形表示把DNA序列转化为时间序列,然后计算DTW距离来度量序列相似度以表征DNA序列属性,得到能够比较DNA序列相似性度量方法,并用这个方法比较分析了七种东亚钳蝎神经毒素(Buthus martensi Karsch neurotoxin)基因序列的相似性,验证了该度量方法的有效性和准确性.
Stiffness matrix for beams with shear deformation and warping torsion
Energy Technology Data Exchange (ETDEWEB)
Schramm, K.; Pilkey, W. [Univ. of Virginia, Charlottesville, VA (United States)
1995-12-31
A beam model which considers the warping effect in beams with arbitrary cross sections is discussed. This model takes into account bending, shear, and warping torsion. The derivation builds on a result in beam theory that, if shear is considered, for arbitrary cross sections the deflections in the different coordinate directions are not uncoupled as has been widely assumed. This conclusion follows from the calculation of the shear coefficients from an elasticity solution using an energy formulation. The shear coefficients form a symmetric tensor. The principal axes for this tensor are called principal shear axes. In Reference 2 structural matrices for the shear problem are derived using these shear coefficients. This paper extends these matrices to warping torsion. St. Venant`s semi-inverse method is applied to calculate warping shear stresses. The usual assumptions of the beam theory are made. The material is linear elastic. The loads may consist of shear forces, axial loads and twisting moments. Small deformations are considered. The cross section of the beam can be of arbitrary shape, thin-walled or solid. A deformation coefficient matrix is calculated which describes the relations between the deformations and the different load cases such as shear, torsion, and warping torsion. Numerical results for warping shear stresses and deformations are given. Also, a method to derive a stiffness matrix for a beam of arbitrary cross section under combined loading including warping torsion is presented.
Language comprehension warps the mirror neuron system.
Zarr, Noah; Ferguson, Ryan; Glenberg, Arthur M
2013-01-01
Is the mirror neuron system (MNS) used in language understanding? According to embodied accounts of language comprehension, understanding sentences describing actions makes use of neural mechanisms of action control, including the MNS. Consequently, repeatedly comprehending sentences describing similar actions should induce adaptation of the MNS thereby warping its use in other cognitive processes such as action recognition and prediction. To test this prediction, participants read blocks of multiple sentences where each sentence in the block described transfer of objects in a direction away or toward the reader. Following each block, adaptation was measured by having participants predict the end-point of videotaped actions. The adapting sentences disrupted prediction of actions in the same direction, but (a) only for videos of biological motion, and (b) only when the effector implied by the language (e.g., the hand) matched the videos. These findings are signatures of the MNS.
Monte Carlo exploration of warped Higgsless models
Energy Technology Data Exchange (ETDEWEB)
Hewett, JoAnne L.; Lillie, Benjamin; Rizzo, Thomas Gerard [Stanford Linear Accelerator Center, 2575 Sand Hill Rd., Menlo Park, CA, 94025 (United States)]. E-mail: rizzo@slac.stanford.edu
2004-10-01
We have performed a detailed Monte Carlo exploration of the parameter space for a warped Higgsless model of electroweak symmetry breaking in 5 dimensions. This model is based on the SU(2){sub L} x SU(2){sub R} x U(1){sub B-L} gauge group in an AdS{sub 5} bulk with arbitrary gauge kinetic terms on both the Planck and TeV branes. Constraints arising from precision electroweak measurements and collider data are found to be relatively easy to satisfy. We show, however, that the additional requirement of perturbative unitarity up to the cut-off, {approx_equal} 10 TeV, in W{sub L}{sup +}W{sub L}{sup -} elastic scattering in the absence of dangerous tachyons eliminates all models. If successful models of this class exist, they must be highly fine-tuned. (author)
Monte Carlo Exploration of Warped Higgsless Models
Hewett, J L; Rizzo, T G
2004-01-01
We have performed a detailed Monte Carlo exploration of the parameter space for a warped Higgsless model of electroweak symmetry breaking in 5 dimensions. This model is based on the $SU(2)_L\\times SU(2)_R\\times U(1)_{B-L}$ gauge group in an AdS$_5$ bulk with arbitrary gauge kinetic terms on both the Planck and TeV branes. Constraints arising from precision electroweak measurements and collider data are found to be relatively easy to satisfy. We show, however, that the additional requirement of perturbative unitarity up to the cut-off, $\\simeq 10$ TeV, in $W_L^+W_L^-$ elastic scattering in the absence of dangerous tachyons eliminates all models. If successful models of this class exist, they must be highly fine-tuned.
Five-Dimensional Warped Geometry with a Bulk Scalar Field
Ito, M
2001-01-01
We explore the diversity of warped metric function in five-dimensional gravity including a scalar field and a 3-brane. We point out that the form of the function is determined by a parameter introduced here. For a particular value of the parameter, the warped metric function is smooth without having a singularity, and we show that the bulk cosmological constant have a upper bound and must be positive and that the lower bound of five-dimensional fundamental scale is controlled by both the brane tension and four-dimensional effective Planck scale. The general warp factor obtained here may relate to models inspired by SUGRA or M-theory.
Tensile Property of Bi-axial Warp Knitted Structure
Institute of Scientific and Technical Information of China (English)
沈为
2003-01-01
The tensile property of bi-axial warp knitted fabrics is tested and compared with that of the plain weave fabric. The results show that there are obvious differences between the tensile property of a bi-axial warp knitted fabric and that of a plain weave fabric.The former can give fuller play to the property of a high modulus yarn than the latter. The tensile strength of a bi-axial warp knitted fabric is linear with the number of yarns in the direction of force.
AN IMPROVED RADIAL BASIS FUNCTION BASED METHOD FOR IMAGE WARPING
Institute of Scientific and Technical Information of China (English)
Nie Xuan; Zhao Rongchun; Zhang Cheng; Zhang Xiaoyan
2005-01-01
A new image warping method is proposed in this letter, which can warp a given image by some manual defined features. Based on the radial basis interpolation function algorithm, the proposed method can transform the original optimized problem into nonsingular linear problem by adding one-order term and affine differentiable condition. This linear system can get the steady unique solution by choosing suitable kernel function. Furthermore, the proposed method demonstrates how to set up the radial basis function in the target image so as to achieve supports to adopt the backward re-sampling technology accordingly which could gain the very slippery warping image. Theexperimental result shows that the proposed method can implement smooth and gradual image warping with multi-anchor points' accurate interpolation.
Asymmetric warps in disk galaxies: dependence on dark matter halo
Jog, K S C J
2006-01-01
Recent observations have shown that most of the warps in the disk galaxies are asymmetric. However there exists no generic mechanism to generate these asymmetries in warps. We have shown that a rich variety of possible asymmetries in the z-distribution of the spiral galaxies can naturally arise due to a dynamical wave interference between the first two bending modes i.e. bowl-shaped mode(m=0) and S-shaped warping mode(m=1) in the galactic disk embedded in a dark matter halo. We show that the asymmetric warps are more pronounced when the dark matter content within the optical disk is lower as in early-type galaxies.
Time Warp Operating System, Version 2.5.1
Bellenot, Steven F.; Gieselman, John S.; Hawley, Lawrence R.; Peterson, Judy; Presley, Matthew T.; Reiher, Peter L.; Springer, Paul L.; Tupman, John R.; Wedel, John J., Jr.; Wieland, Frederick P.;
1993-01-01
Time Warp Operating System, TWOS, is special purpose computer program designed to support parallel simulation of discrete events. Complete implementation of Time Warp software mechanism, which implements distributed protocol for virtual synchronization based on rollback of processes and annihilation of messages. Supports simulations and other computations in which both virtual time and dynamic load balancing used. Program utilizes underlying resources of operating system. Written in C programming language.
Optimization Design of Warping Dam in Wangjiagou, Shanxi Province
Institute of Scientific and Technical Information of China (English)
Zhang Yu; Cui Peng; Li Fa-bin; Wang Qing
2003-01-01
This paper introduces the simulating design of warping dam in the Loess Plateau, western Shanxi province.On the basis of collected data, the digital elevation model in the studied area has been created. Utilizing GIS (geographical information system) technology, this paper achieves some environmental based results with the simulation method. Also based on the parameter model of precipitation, the tendency of warping sand has been calculated, aiming at providing academic basis for optimization design in the small watershed.
Optimization Design of Warping Dam in Wangjiagou, Shanxi Province
Institute of Scientific and Technical Information of China (English)
ZhangYu; CuiPeng; LiFa-bin; WangQing
2003-01-01
This paper introduces the simulating design of warping dam in the Loess Plateau, western Shanxi province.On the basis of collected data, the digital elevation model in the studied area has been created. Utilizing GIS (geographical information system) technology, this paper achieves some environrnental based results with the simulation method. Also based on the parameter model of precipitation, the tendency of warping sand has been calculated, aiming at providing academic basis for optimization design in the small watershed.
Time Warp Operating System, Version 2.5.1
Bellenot, Steven F.; Gieselman, John S.; Hawley, Lawrence R.; Peterson, Judy; Presley, Matthew T.; Reiher, Peter L.; Springer, Paul L.; Tupman, John R.; Wedel, John J., Jr.; Wieland, Frederick P.; Younger, Herbert C.
1993-01-01
Time Warp Operating System, TWOS, is special purpose computer program designed to support parallel simulation of discrete events. Complete implementation of Time Warp software mechanism, which implements distributed protocol for virtual synchronization based on rollback of processes and annihilation of messages. Supports simulations and other computations in which both virtual time and dynamic load balancing used. Program utilizes underlying resources of operating system. Written in C programming language.
On the generation of asymmetric warps in disk galaxies
Saha, K; Saha, Kanak; Jog, Chanda J.
2005-01-01
The warps in many spiral galaxies are now known to asymmetric. Recent sensitive observations have revealed that asymmetry of warps may be the norm rather than exception. However there exists no generic mechanism to generate these asymmetries in warps. We have derived the dispersion relation in a compact form for the S-shaped warps(described by the m=1 mode) and the bowl-shaped distribution(described by the m=0 mode) in galactic disk embedded in a dark matter halo. We then performed the numerical modal analysis and used the linear and time-dependent superposition principle to generate asymmetric warps in the disk. On doing the modal analysis we find the frequency of the $m=0$ mode is much larger than that of the $m=1$ mode. The linear and time-dependent superposition of these modes with their unmodulated amplitudes(that is, the coefficients of superposition being unity) results in an asymmetry in warps of ~ 20 - 40 %, whereas a smaller coefficient for the m=0 mode results in a smaller asymmetry. The resulting ...
Multichannel Dynamic-Range Compression Using Digital Frequency Warping
Directory of Open Access Journals (Sweden)
Kathryn Hoberg Arehart
2005-11-01
Full Text Available A multichannel dynamic-range compressor system using digital frequency warping is described. A frequency-warped filter is realized by replacing the filter unit delays with all-pass filters. The appropriate design of the frequency warping gives a nonuniform frequency representation very close to the auditory Bark scale. The warped compressor is shown to have substantially reduced group delay in comparison with a conventional design having comparable frequency resolution. The warped compressor, however, has more delay at low than at high frequencies, which can lead to perceptible changes in the signal. The detection threshold for the compressor group delay was determined as a function of the number of all-pass filter sections in cascade needed for a detectible change in signal quality. The test signals included clicks, vowels, and speech, and results are presented for both normal-hearing and hearing-impaired subjects. Thresholds for clicks are lower than thresholds for vowels, and hearing-impaired subjects have higher thresholds than normal-hearing listeners. A frequency-warped compressor using a cascade of 31 all-pass filter sections offers a combination of low overall delay, good frequency resolution, and imperceptible frequency-dependent delay effects for most listening conditions.
Influence of Warp Yarn Tension on Cotton Woven Fabric Structures
Directory of Open Access Journals (Sweden)
Uzma Syed
2013-01-01
Full Text Available Control of the warp and weft yarn tension is an important factor. In this research, effect of warp yarn tension variations on the quality of greige and dyed woven fabrics was investigated. Six fabric samples (three Plain and three Twill weaves were woven on shuttle loom at varied warp yarn tension. The fabric samples were then pre-treated and dyed (Drimarene Red Cl 5B, 3% owf using laboratory singeing machine and HT dyeing machine. Greige fabric quality such as fabric inspection, fabric length, fabric width, GSM (Gram per Square Meter, EPI (Ends per Inch, PPI (Picks per Inch, and dyed fabric quality such as L*, a*, b*, C, h o , (K/S ?max and fastness properties were assessed according to the standard. It has been observed that fabric samples, both Plain and Twill weave; woven at improper warp yarns tension gives rejected greige fabric quality and 1-7% lower (K/S 550nm values as compared to the fabric weave at requisite warp yarn tension such as 38-39cN for Plain fabric and 78cN for Twill fabric for 42x38 and 64x36 tex construction. Hence, among other weave faults, warp yarn tension variation has influence on the greige fabric quality as well as caused improper and uneven dyeing behavior.
Unified flavor symmetry from warped dimensions
Directory of Open Access Journals (Sweden)
Mariana Frank
2015-03-01
Full Text Available In a model of warped extra-dimensions with all matter fields in the bulk, we propose a scenario which explains all the masses and mixings of the SM fermions. In this scenario, the same flavor symmetric structure is imposed on all the fermions of the Standard Model (SM, including neutrinos. Due to the exponential sensitivity on bulk fermion masses, a small breaking of this symmetry can be greatly enhanced and produce seemingly un-symmetric hierarchical masses and small mixing angles among the charged fermion zero-modes (SM quarks and charged leptons, thus washing out visible effects of the symmetry. If the Dirac neutrinos are sufficiently localized towards the UV boundary, and the Higgs field leaking into the bulk, the neutrino mass hierarchy and flavor structure will still be largely dominated and reflect the fundamental flavor structure, whereas localization of the quark sector would reflect the effects of the flavor symmetry breaking sector. We explore these features in an example based on which a family permutation symmetry is imposed in both quark and lepton sectors.
The Curious Case of Null Warped Space
Anninos, Dionysios; de Buyl, Sophie; Detournay, Stéphane; Guica, Monica
2010-01-01
We initiate a comprehensive study of a set of solutions of topologically massive gravity known as null warped anti-de Sitter spacetimes. These are pp-wave extensions of three-dimensional anti-de Sitter space. We first perform a careful analysis of the linearized stability of black holes in these spacetimes. We find two qualitatively different types of solutions to the linearized equations of motion: the first set has an exponential time dependence, the second - a polynomial time dependence. The solutions polynomial in time induce severe pathologies and moreover survive at the non-linear level. In order to make sense of these geometries, it is thus crucial to impose appropriate boundary conditions. We argue that there exists a consistent set of boundary conditions that allows us to reject the above pathological modes from the physical spectrum. The asymptotic symmetry group associated to these boundary conditions consists of a centrally-extended Virasoro algebra. Using this central charge we can account for th...
Diphoton Resonance from a Warped Extra Dimension
Bauer, Martin; Neubert, Matthias
2016-01-01
We argue that extensions of the Standard Model (SM) with a warped extra dimension, which successfully address the hierarchy and flavor problems of elementary particle physics, can provide an elegant explanation of the 750 GeV diphoton excess recently reported by ATLAS and CMS. A gauge-singlet bulk scalar with O(1) couplings to fermions is identified as the new resonance S, and the vector-like Kaluza-Klein excitations of the SM quarks and leptons mediate its loop-induced couplings to photons and gluons. The electroweak gauge symmetry almost unambiguously dictates the bulk matter content and hence the hierarchies of the S->\\gamma\\gamma, WW, ZZ, Z\\gamma, t\\bar t and dijet decay rates. We find that the S->Z\\gamma decay mode is strongly suppressed, such that Br(S->Z\\gamma)Br(S->\\gamma\\gamma)S->\\gamma\\gamma signal requires Kaluza-Klein masses in the multi-TeV range, in perfect agreement with bounds from flavor physics and electroweak precision observables.
Diphoton resonance from a warped extra dimension
Bauer, Martin; Hörner, Clara; Neubert, Matthias
2016-07-01
We argue that extensions of the Standard Model (SM) with a warped extra dimension, which successfully address the hierarchy and flavor problems of elementary particle physics, can provide an elegant explanation of the 750 GeV diphoton excess recently reported by ATLAS and CMS. A gauge-singlet bulk scalar with {O} (1) couplings to fermions is identified as the new resonance S, and the vector-like Kaluza-Klein excitations of the SM quarks and leptons mediate its loop-induced couplings to photons and gluons. The electroweak gauge symmetry almost unambiguously dictates the bulk matter content and hence the hierarchies of the Sto γ γ, W W,ZZ,Zγ, toverline{t} and dijet decay rates. We find that the S → Zγ decay mode is strongly suppressed, such that Br( S → Zγ) /Br( S → γγ) converge and can be calculated in closed form with a remarkably simple result. Reproducing the observed pp → S → γγ signal requires Kaluza-Klein masses in the multi-TeV range, consistent with bounds from flavor physics and electroweak precision observables.
LHC Signals from Warped Extra Dimensions
Energy Technology Data Exchange (ETDEWEB)
Agashe, K.; Belyaev, A.; Krupovnickas, T.; Perez, G.; Virzi, J.
2006-12-06
We study production of Kaluza-Klein gluons (KKG) at the Large Hadron Collider (LHC) in the framework of a warped extra dimension with the Standard Model (SM) fields propagating in the bulk. We show that the detection of KK gluon is challenging since its production is suppressed by small couplings to the proton's constituents. Moreover, the KK gluon decaysmostly to top pairs due to an enhanced coupling and hence is broad. Nevertheless, we demonstrate that for MKKG<~;; 4 TeV, 100 fb-1 of data at the LHC can provide discovery of the KK gluon. We utilize a sizeable left-right polarization asymmetry from the KK gluon resonance to maximize the signal significance, and we explore the novel feature of extremely highly energetic"top-jets." We briefly discuss how the detection of electroweak gauge KK states (Z/W) faces a similar challenge since their leptonic decays ("golden" modes) are suppressed. Our analysis suggests that other frameworks, for example little Higgs, which rely on UV completion via strong dynamics might face similar challenges, namely (1) Suppressed production rates for the new particles (such as Z'), due to their"lightfermion-phobic" nature, and (2) Difficulties in detection since the new particles are broad and decay predominantly to third generation quarks and longitudinal gauge bosons.
Spatial warping by oriented line detectors can counteract neural delays
Directory of Open Access Journals (Sweden)
Don eVaughn
2013-11-01
Full Text Available The slow speed of neural transmission necessitates that cortical visual information from dynamic scenes will lag reality. The perceiving the present (PTP hypothesis suggests that the visual system can mitigate the effect of such delays by spatially warping scenes to look as they will in ~100 ms from now (Changizi, 2001. We here show that the Hering illusion, in which straight lines appear bowed, can be induced by a background of optic flow, consistent with the PTP hypothesis. However, importantly, the bowing direction is the same whether the flow is inward or outward. This suggests that if the warping is meant to counteract latencies, it is accomplished by a simple strategy that is insensitive to motion direction, and that works only under typical (forward-moving circumstances. We also find that the illusion strengthens with longer pulses of optic flow, demonstrating motion integration over ~80 ms. The illusion is identical whether optic flow precedes or follows the flashing of bars, exposing the spatial warping to be equally postdictive and predictive, i.e., peri-dictive. Additionally, the illusion is diminished by cues which suggest the bars are independent of the background movement. Collectively, our findings are consistent with a role for networks of visual orientation-tuned neurons (e.g., simple cells in primary visual cortex in spatial warping. We conclude that under the common condition of forward ego-motion, spatial warping counteracts the disadvantage of neural latencies. It is not possible to prove that this is the purpose of spatial warping, but our findings at minimum place constraints on the PTP hypothesis, demonstrating that any spatial warping for the purpose of counteracting neural delays is not a precise, on-the-fly computation, but instead a heuristic achieved by a simple mechanism that succeeds under normal circumstances.
Warp diffusion in accretion discs: a numerical investigation
Lodato, Giuseppe
2007-01-01
In this paper we explore numerically the evolution of a warped accretion disc. Here, we focus here on the regime where the warp evolves diffusively. By comparing the numerical results to a simple diffusion model, we are able to determine the diffusion coefficient of the warp, $\\alpha_2$, as a function of the relevant disc parameters. We find that while in general the disc behaviour is well reproduced by the diffusion model and for relatively large viscosities the warp diffusion is well described by the linear theory (in particular confirming that the warp diffusion coefficient is inversely proportional to viscosity), significant non-linear effects are present as the viscosity becomes smaller, but still dominates over wave-propagation effects. In particular, we find that the inverse dependence of the diffusion coefficient on viscosity breaks down at low viscosities, so that $\\alpha_2$ never becomes larger than a saturation value $\\alpha_{\\rm max}$ of order unity. This can have major consequences in the evoluti...
Constraining the age of the NGC 4565 H I disk WARP: Determining the origin of gas WARPS
Energy Technology Data Exchange (ETDEWEB)
Radburn-Smith, David J.; Dalcanton, Julianne J.; Stilp, Adrienne M. [Department of Astronomy, University of Washington, Seattle, WA 98195 (United States); De Jong, Roelof S.; Streich, David [Leibniz-Institut für Astrophysik Potsdam, D-14482 Potsdam (Germany); Bell, Eric F.; Monachesi, Antonela [Department of Astronomy, University of Michigan, Ann Arbor, MI 48109 (United States); Dolphin, Andrew E. [Raytheon, 1151 East Hermans Road, Tucson, AZ 85756 (United States); Holwerda, Benne W. [European Space Agency, ESTEC, 2200 AG Noordwijk (Netherlands); Bailin, Jeremy [Department of Physics and Astronomy, University of Alabama, Tuscaloosa, AL 35487 (United States)
2014-01-01
We have mapped the distribution of young and old stars in the gaseous H I warp of NGC 4565. We find a clear correlation of young stars (<600 Myr) with the warp but no coincident old stars (>1 Gyr), which places an upper limit on the age of the structure. The formation rate of the young stars, which increased ∼300 Myr ago relative to the surrounding regions, is (6.3{sub −1.5}{sup +2.5})×10{sup −5} M {sub ☉} yr{sup –1} kpc{sup –2}. This implies a ∼60 ± 20 Gyr depletion time of the H I warp, similar to the timescales calculated for the outer H I disks of nearby spiral galaxies. While some stars associated with the warp fall into the asymptotic giant branch (AGB) region of the color-magnitude diagram, where stars could be as old as 1 Gyr, further investigation suggests that they may be interlopers rather than real AGB stars. We discuss the implications of these age constraints for the formation of H I warps and the gas fueling of disk galaxies.
Time-Dependent Warping and Non-Singular Bouncing Cosmologies
Balasubramanian, Koushik
2014-01-01
In this note, we construct a family of non-singular time-dependent solutions of a six-dimensional gravitational theory that are warped products of a four dimensional bouncing cosmological solution and a two dimensional internal manifold. The warp factor is time-dependent and breaks translation invariance along one of the internal directions. When the warp factor is periodic in time, the non-compact part of the geometry bounces periodically. The six dimensional geometry is supported by matter that does not violate the null energy condition. We show that this 6D geometry does not admit a closed trapped surface and hence the Hawking-Penrose singularity theorems do not apply to these solutions. We also present examples of singular solutions where the topology of the internal manifold changes dynamically.
Modulus stabilization in a non-flat warped braneworld scenario
Energy Technology Data Exchange (ETDEWEB)
Banerjee, Indrani [S.N. Bose National Centre for Basic Sciences, Department of Astrophysics and Cosmology, Kolkata (India); SenGupta, Soumitra [Indian Association for the Cultivation of Science, Department of Theoretical Physics, Kolkata (India)
2017-05-15
The stability of the modular field in a warped brane world scenario has been a subject of interest for a long time. Goldberger and Wise (GW) proposed a mechanism to achieve this by invoking a massive scalar field in the bulk space-time neglecting the back-reaction. In this work, we examine the possibility of stabilizing the modulus without bringing about any external scalar field. We show that instead of flat 3-branes as considered in Randall-Sundrum (RS) warped braneworld model, if one considers a more generalized version of warped geometry with de Sitter 3-brane, then the brane vacuum energy automatically leads to a modulus potential with a metastable minimum. Our result further reveals that in this scenario the gauge hierarchy problem can also be resolved for an appropriate choice of the brane's cosmological constant. (orig.)
I-WARP: Individual Water mAin Renewal Planner
Directory of Open Access Journals (Sweden)
Y. Kleiner
2010-05-01
Full Text Available I-WARP is based upon a nonhomogeneous Poisson approach to model breakage rates in individual water mains. The structural deterioration of water mains and their subsequent failure are affected by many factors, both static (e.g., pipe material, pipe size, age (vintage, soil type and dynamic (e.g., climate, cathodic protection, pressure zone changes. I-WARP allows for the consideration of both static and dynamic factors in the statistical analysis of historical breakage patterns. This paper describes the mathematical approach and demonstrates its application with the help of a case study. The research project within which I-WARP was developed, was jointly funded by the National Research Council of Canada (NRC, and the Water Research foundation (formerly known as the American Water Works Association Research Foundation – AwwaRF and supported by water utilities from USA and Canada.
On higher dimensional Einstein spacetimes with a warped extra dimension
Ortaggio, Marcello; Pravdova, Alena
2010-01-01
We study higher dimensional Einstein spacetimes that can be mapped conformally on other Einstein spacetimes. These admit a simple warped line element (with one extra dimension) that was originally introduced by Brinkmann and that has subsequently appeared in various contexts to describe, e.g., different braneworld models or warped black strings. After clarifying the relation between the general Brinkmann metric and other more specific coordinate systems, we analyze the algebraic type of the Weyl tensor of the solutions. In particular, we describe the relation between Weyl aligned null directions (WANDs) of the lower dimensional Einstein slices and of the full spacetime, which in some cases can be algebraically more special. Possible spacetime singularities introduced by the warp factor are determined via a study of scalar curvature invariants and of Weyl components measured by geodetic observers. Finally, we illustrate how Brinkmann's metric can be employed to generate new solutions by presenting the metric o...
Holographic entropy of Warped-AdS$_3$ black holes
Donnay, Laura
2015-01-01
We study the asymptotic symmetries of three-dimensional Warped Anti-de Sitter (WAdS) spaces in three-dimensional New Massive Gravity (NMG). For a specific choice of asymptotic boundary conditions, we find that the algebra of charges is infinite-dimensional and coincides with the semidirect sum of Virasoro algebra with non-vanishing central charge and an affine $\\hat{u}(1)_k$ Ka\\v{c}-Moody algebra. We show that the WAdS black hole configurations organize in terms of two commuting Virasoro algebras. We identify the Virasoro generators that expand the associated representations in the dual Warped Conformal Field Theory (WCFT) and, by applying the Warped version of the Cardy formula, we prove that the microscopic WCFT computation exactly reproduces the entropy of black holes in WAdS space.
Warped-AdS3 black holes with scalar halo
Giribet, Gaston
2015-01-01
We construct a stretched (aka Warped) Anti-de Sitter black hole in 3 dimensions supported by a real scalar field configuration. The latter is regular everywhere outside and on the horizon. No hair theorems in 3 dimensions demand the matter to be coupled to the curvature in a non-minimal way; however, this coupling can still be of the Horndeski type, i.e. yielding second order field equations similar to those appearing in the context of Galileon theories. These Warped-Anti-de Sitter black holes exhibit interesting thermodynamical properties, such as finite Hawking temperature and entropy. We compute the black hole entropy in the gravity theory and speculate with the possibility of this to admit a microscopic description in terms of a dual (Warped) Conformal Field Theory. We also discuss the inner and outer black hole mechanics.
Cotton/polyester and cotton/nylon warp knitted terry cloth: Why ...
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warp knitting machine, using three sets of warp yarns. (Hatch, 1993:358; Kadolph ..... facturing and Materials Technology Centre for Fibres,. Textiles and Clothing ... interpreted if the interaction effects were not signifi- cant; otherwise various ...
Arbitrary Phase Vocoders by means of Warping
Directory of Open Access Journals (Sweden)
Gianpaolo Evangelista
2013-08-01
Full Text Available The Phase Vocoder plays a central role in sound analysis and synthesis, allowing us to represent a sound signal in both time and frequency, similar to a music score – but possibly at much finer time and frequency scales – describing the evolution of sound events. According to the uncertainty principle, time and frequency are not independent variables so that any time-frequency representation is the result of a compromise between time and frequency resolutions, the product of which cannot be smaller than a given constant. Therefore, finer frequency resolution can only be achieved with coarser time resolution and, similarly, finer time resolution results in coarser frequency resolution.While most of the conventional methods for time-frequency representations are based on uniform time and uniform frequency resolutions, perception and physical characteristics of sound signals suggest the need for nonuniform analysis and synthesis. As the results of psycho-acoustic research show, human hearing is naturally organized in nonuniform frequency bands. On the physical side, the sounds of percussive instruments as well as piano in the low register, show partials whose frequencies are not uniformly spaced, as opposed to the uniformly spaced partial frequencies found in harmonic sounds. Moreover, the different characteristics of sound signals at the onset transients with respect to stationary segments suggest the need for nonuniform time resolution. In the effort to exploit the time-frequency resolution compromise at its best, a tight time-frequency suit should be tailored to snuggly fit the sound body.In this paper we overview flexible design methods for phase vocoders with nonuniform resolutions. The methods are based on remapping the time or the frequency axis, or both, by employing suitable functions acting as warping maps, which locally change the characteristics of the time-frequency plane. As a result, the sliding windows may have time dependent
Development of Warp Knitted Products on RSJ Machine
Institute of Scientific and Technical Information of China (English)
XU Dong-ping; LI Wei; FENG Xun-wei
2007-01-01
Products made by Raschel Jacquard(RSJ) high-speed jacquard warp knitting machine are used in ornamentand apparel fabrics. However, most products are producedaccording to the existing samples. The capability of creativedesign is not enough at home. In this paper, based on thebasic features, the knitting methods and the workingprinciples of warp knitting jacquard machines, the rules formanufacturing jacquard products are summarized. Thearticle provides the new thoughts for the development offabrics, such as the pattern design, changing the cams,power-net and a special technology of without pillar, whichwere obtained from the practices in a factory.
Positions of Guide Eyes in Circular Warp Knitting Machines
Institute of Scientific and Technical Information of China (English)
GU Zhao-wen
2002-01-01
The special lapping requirements were pointed out and the safe range to fix the guide eyes on the circular guide unit was determined by means of Locus Formulas of Warp sections in lapping movement, which were carried out on installing prototype machine. Based on the calculations of the force components acting on lapping points, the positions of the guide eyes in chain overlapping could be used to determine the safe range that could meet the requirements for tricot overlapping.The safe range can ensure the successful lapping and the multi-guide unit designing in circular warp-knitting machines.
The origin of the warped heliospheric current sheet
Wilcox, J. M.; Scherrer, P. H.; Hoeksema, J. T.
1980-03-01
The warped heliospheric current sheet in early 1976 was calculated from the observed photospheric magnetic field using a potential field method. Comparisons with measurements of the interplanetary magnetic field polarity in early 1976 obtained at several locations in the heliosphere at Helios 1, Helios 2, Pioneer 11 and Earth show a rather detailed agreement between the computed current sheet and the observations. It appears that the large scale structure of the warped heliospheric current sheet is determined by the structure of the photospheric magnetic field, and that "ballerina skirt" effects may add small scale ripples.
A review of recent developments in warp sizing
CSIR Research Space (South Africa)
McMahon, JF
1985-08-01
Full Text Available .................................................. REFERENCES 30 A REVIEW OF RECENT DEVELOPMENTS IN WARP S r n G by J FMeMahon and G H J van der Walt cnAPrER1 INTRODUCIlON The function of sizing is to improve weavabiity by protecting the warp yarns from abrasion in the healds and reed and against each... shuttle looms and eventually the modem shuttleless weaving machine, improved sizing materials were required. This led to the development of chemically modified starches and new synthetic polymers. The introduction of these materials resulted...
Living on the edge in a spacetime with multiple warping
Choudhury, D; Choudhury, Debajyoti; Gupta, Soumitra Sen
2006-01-01
The Randall-Sundrum warped braneworld model is generalised to six and higher dimensions such that the warping has a non-trivial dependence on more than one dimension. This naturally leads to a brane-box like configuration alongwith scalar fields with possibly interesting cosmological roles. Also obtained naturally are two towers of 3 branes with mass scales clustered around either of Planck scale and TeV scale. Such a scenario has interesting phenomenological consequences including an explanation for the observed hierarchy in the masses of standard model fermions.
Warped Angle-deficit of a 5 Dimensional Cosmic String
Slagter, Reinoud Jan; Masselink, Derk
2011-01-01
We present a cosmic string on a warped five dimensional space time in Einstein-Yang-Mills theory. Four-dimensional cosmic strings show some serious problems concerning the mechanism of string smoothing related to the string mass per unit length, $G\\mu \\approx 10^{-6}$. A warped cosmic string could overcome this problem and also the superstring requirement that $G\\mu$ must be of order 1, which is far above observational bounds. Also the absence of observational evidence of axially symmetric le...
Radiative transfer modelling of parsec-scale dusty warped discs
Jud, H; Mould, J; Burtscher, L; Tristram, K R W
2016-01-01
Warped discs have been found on (sub-)parsec scale in some nearby Seyfert nuclei, identified by their maser emission. Using dust radiative transfer simulations we explore their observational signatures in the infrared in order to find out whether they can partly replace the molecular torus. Strong variations of the brightness distributions are found, depending on the orientation of the warp with respect to the line of sight. Whereas images at short wavelengths typically show a disc-like and a point source component, the warp itself only becomes visible at far-infrared wavelengths. A similar variety is visible in the shapes of the spectral energy distributions. Especially for close to edge-on views, the models show silicate feature strengths ranging from deep absorption to strong emission for variations of the lines of sight towards the warp. To test the applicability of our model, we use the case of the Circinus galaxy, where infrared interferometry has revealed a highly elongated emission component matching ...
Wing Warping and Its Impact on Aerodynamic Efficiency
Loh, Ben; Jacob, Jamey
2007-11-01
Inflatable wings have been demonstrated in many applications such as UAVs, airships, and missile stabilization surfaces. A major concern presented by the use of an inflatable wing has been the lack of traditional roll control surfaces. This leaves the designer with several options in order to have control about the roll axis. Since inflatable wings have a semi-flexible structure, wing warping is the obvious solution to this problem. The current method is to attach servos and control linkages to external surface of the wing that results in variation of profile chamber and angle of attack from leading edge or trailing edge deflection. Designs using internal muscles will also be discussed. This creates a lift differential between the half-spans, resulting in a roll moment. The trailing edge on the other half-span can also be deflected in the opposite direction to increase the roll moment as well as to reduce roll-yaw coupling. Comparisons show that higher L/D ratios are possible than using traditional control surfaces. An additional benefit is the ability to perform symmetric warping to achieve optimum aerodynamic performance. Via warping alone, an arbitrary span can be warped such that it has the same aerodynamic characteristics as an elliptical planform. Comparisons between lifting line theory and test results will be presented.
Interactions between massive dark halos and warped disks
Kuijken, K; Persic, M; Salucci, P
1997-01-01
The normal mode theory for warping of galaxy disks, in which disks are assumed to be tilted with respect to the equator of a massive, flattened dark halo, assumes a rigid, fixed halo. However, consideration of the back-reaction by a misaligned disk on a massive particle halo shows there to be strong
SUSY properties of warped AdS3
Jeong, Jaehoon; Colgáin, Eoin Ó.; Yoshida, Kentaroh
2014-06-01
We examine supersymmetric properties of null-warped AdS3, or alternatively Schrödinger geometries, dual to putative warped CFTs in two dimensions. We classify super Schrödinger subalgebras of the superalgebra psu(1, 1|2) ⊕ psu(1, 1|2), corresponding to the superconformal algebra of the AdS3 × S3 geometry. We comment on geometric realisations and provide a string theory description with enhanced supersymmetry in terms of intersecting D3-branes. For type IIB supergravity solutions based on T 1,1, we consider the relationship between five-dimensional Schrödinger solutions and their three-dimensional null-warped counterparts, corresponding to R symmetry twists. Finally, we study a family of null-warped AdS3 solutions in a setting where there is an ambiguity over the R symmetry and confirm that, for examples admitting a Kaluza-Klein (KK) reduction to three dimensions, the minimisation of a real superpotential of the three-dimensional gauged supergravity captures the central charge and R symmetry.
Induced dark energy in a warped braneworld and accelerating universe
Lee, Tae Hoon
2016-10-01
In the six-dimensional (6D) Einstein gravity with a negative cosmological constant, we determine the structure of warped spacetimes bounded by 4-branes. We find an accelerating Universe solution with the induced dark energy, from the 4-brane obtained by orbifolding an external space, and suggest a possibility of addressing problems related to the cosmological constant.
Hopfing and Puffing Warped Anti-de Sitter Space
Anninos, Dionysios
2009-01-01
Three dimensional spacelike warped anti-de Sitter space is studied in the context of Einstein theories of gravity and string theory, where there is no gravitational Chern-Simons term in the action. We propose that it is holographically dual to a two-dimensional conformal field theory with equal left and right moving central charges. Various checks of the central charges are offered, based on the Bekenstein-Hawking entropy of the stretched warped black holes and warped self-dual solutions. The proposed central charges are applied to compute the Bekenstein-Hawking entropy of the Hopf T-dual of six-dimensional dyonic black strings which have a near horizon consisting of three dimensional warped anti-de Sitter space times a three-sphere. We find that the Hopf T-duality is a map between thermal states with equal entropy of the CFTs dual to the dyonic black string and the Hopf T-dualized black string.
Effective action for a quantum scalar field in warped spaces
Energy Technology Data Exchange (ETDEWEB)
Hoff da Silva, J.M.; Mendonca, E.L.; Scatena, E. [Universidade Estadual Paulista ' ' Julio de Mesquita Filho' ' -UNESP, Departamento de Fisica e Quimica, Guaratingueta, SP (Brazil)
2015-11-15
We investigate the one-loop corrections, at zero as well as finite temperature, of a scalar field taking place in a braneworld motivated warped background. After to reach a well-defined problem, we calculate the effective action with the corresponding quantum corrections to each case. (orig.)
Conformal Gravity and the Alcubierre Warp Drive Metric
Varieschi, Gabriele U
2012-01-01
We present an analysis of the classic Alcubierre metric based on conformal gravity, rather than standard general relativity. The main characteristics of the resulting warp drive remain the same as in the original study by Alcubierre, namely that effective super-luminal motion is a viable outcome of the metric. We show that for particular choices of the shaping function, the Alcubierre metric in the context of conformal gravity does not violate the weak energy condition, as was the case of the original solution. In particular, the resulting warp drive does not require the use of exotic matter. Therefore, if conformal gravity is a correct extension of general relativity, super-luminal motion via an Alcubierre metric might be a realistic solution, thus allowing faster-than-light interstellar travel.
Warped Geometry in Higher Dimensions with an Orbifold Extra Dimension
Ito, M
2001-01-01
We solve the Einstein equations in higher dimensions with warped geometry where an extra dimension is assumed to have orbifold symmetry, $S^{1}/Z_{2}$. The setup we consider here is an extension to (5+D)-dimensions of the 5-dimensional Randall-Sundrum model, and two hidden brane and observable brane are fixed on orbifold. Anisotropic cosmological constant on each brane with (4+D)-dimensional spacetime is assumed, and the warped metric of 4-dimensions is generally different from one of extra D-dimensions. It is pointed out that the form of metric depends on both the sign of bulk cosmological constant and initial condition of brane world. Furthermore, anisotropic cosmological constant on each brane can be realized due to the presence of brane.
Multicusp caustics formed from reflections of warped surfaces.
Theocaris, P S
1988-02-15
The optical method of caustics developed mainly for studying singularities in stress fields was extended to define quantitatively the slope variation of warped surfaces. The existing theory was concerned with the study of infinitesimal but abrupt variations of thickness in elastic and plastic stress fields containing stress singularities due to either loading or geometry. In this paper the theory of caustics was extended to study the warping of any surface due mainly to twisting loads- While the caustics developed in previous uses were generalized epicycloid surfaces with or without a single cusp line, in the cases studied in this paper multicusp surfaces were developed. The quantitative interrelationship between the shape and size of the caustic and the respective mode of twisting of the surface was established, and interesting properties of these surfaces were disclosed. Applications to twisted elliptic, triangular, and square elastic bars clearly illustrate the importance of the method.
Wing Warping, Roll Control and Aerodynamic Optimization of Inflatable Wings
Simpson, Andrew
2005-11-01
The research presents work on aerodynamic control by warping inflatable wings. Inflatable wings are deformable by their nature. Mechanical manipulation of the wing's shape has been demonstrated to alter the performance and control the vehicle in flight by deforming the trailing edge of the wing near the wing tip. Predicting and correlating the forces required in deforming the wings to a particular shape and the deformation generated for a given internal pressure were conducted through the use of photogrammetry. This research focuses on optimizing the roll moments and aerodynamic performance of the vehicle, given the current level of wing warping ability. Predictions from lifting line theory applied to wing shape changes are presented. Comparisons from the experimental results are made with lifting line analysis for wings with arbitrary twist and the solutions are used to determine rolling moment and optimum L/D. Results from flight tests will also be presented.
A method and apparatus for sizing and separating warp yarns
Energy Technology Data Exchange (ETDEWEB)
Sheen, Shuh-Haw; Chien, Hual-Te; Raptis, Apostolos C.; Kupperman, David S.
1997-12-01
A slashing process for preparing warp yarns for weaving operations includes the steps of sizing and/or desizing the yarns in an acoustic resonance box and separating the yarns with a leasing apparatus comprised of a set of acoustically agitated lease rods. The sizing step includes immersing the yarns in a size solution contained in an acoustic resonance box. Acoustic transducers are positioned against the exterior of the box for generating an acoustic pressure field within the size solution. Ultrasonic waves that result from the acoustic pressure field continuously agitate the size solution to effect greater mixing and more uniform application and penetration of the size onto the yarns. The sized yarns are then separated by passing the warp yarns over and under lease rods. Electroacoustic transducers generate acoustic waves along the longitudinal axis of the lease rods, creating a shearing motion on the surface of the rods for splitting the yarns.
On the impossibility of superluminal travel: the warp drive lesson
Barceló, Carlos; Liberati, Stefano
2010-01-01
The question of whether it is possible or not to surpass the speed of light is already centennial. The special theory of relativity took the existence of a speed limit as a principle, the light postulate, which has proven to be enormously predictive. Here we discuss some of its twists and turns when general relativity and quantum mechanics come into play. In particular, we discuss one of the most interesting proposals for faster than light travel: warp drives. Even if one succeeded in creating such spacetime structures, it would be still necessary to check whether they would survive to the switching on of quantum matter effects. Here, we show that the quantum back-reaction to warp-drive geometries, created out of an initially flat spacetime, inevitably lead to their destabilization whenever superluminal speeds are attained. We close this investigation speculating the possible significance of this further success of the speed of light postulate.
Dynamic time warping for temperature compensation in structural health monitoring
Douglass, Alexander; Harley, Joel B.
2017-02-01
Guided wave structural health monitoring uses ultrasonic waves to identify changes in structures. To identify these changes, most guided wave methods require a pristine baseline measurement with which other measurements are compared. Damage signatures arise when there is a deviation between the baseline and the recorded measurement. However, temperature significantly complicates this analysis by creating misalignment between the baseline and measurements. This leads to false alarms of damage and significantly reduces the reliability of these systems. Several methods have been created to account for these temperature perturbations. Yet, most of these compensation methods fail in harsh, highly variable temperature conditions or require a prohibitive amount of prior data. In this paper, we use an algorithm known as dynamic time warping to compensate for temperature in these harsh conditions. We demonstrate that dynamic time warping is able to account for temperature variations whereas the more traditional baseline signal stretch method is unable to resolve damage under high temperature fluctuations.
WARPING AND PRECESSION IN EXTRAGALACTIC MASER ACCRETION DISCS
Directory of Open Access Journals (Sweden)
A. Caproni
2009-01-01
Full Text Available Interferometric maser observations have been used to probe the physical conditions of extragalactic accretion discs at sub-parsec scales. The inferred kinematic of the water maser spots presents small deviations from Keplerian motions, which have been attributed to the warping and twisting of the parsec-scale disc. However, their physical origin is still a matter of debate in the literature. Motivated by this, we analyzed the general relativistic Bardeen-Petterson e ect, driven by a Kerr black hole, as the potential physical mechanism responsible for the disc warping and precession in the nearby Seyfert 2 galaxies NGC 1068 and NGC 4258. Assuming a power-law accretion disc, whose parameters were constrained by the observational data, we derived the basic quantities concerning the Bardeen-Petterson e ect for both sources. Some consequences from this peculiar relativistic mechanism are also presented in this work.
Multi-flux warped throats and cascading gauge theories
Franco, S; Uranga, Angel M; Franco, Sebastian; Hanany, Amihay; Uranga, Angel M.
2005-01-01
We describe duality cascades and their infrared behavior for systems of D3-branes at singularities given by complex cones over del Pezzo surfaces (and related examples), in the presence of fractional branes. From the gauge field theory viewpoint, we show that D3-branes probing the infrared theory have a quantum deformed moduli space, given by a complex deformation of the initial geometry to a simpler one. This implies that for the dual supergravity viewpoint, the gauge theory strong infrared dynamics smoothes out the naked singularities of the recently constructed warped throat solutions with 3-form fluxes, describing the cascading RG flow of the gauge theory. This behavior thus generalizes the Klebanov-Strassler deformation of the conifold. We describe several explicit examples, including models with several scales of strong gauge dynamics. In the regime of widely separated scales, the dual supergravity solutions should correspond to throats with several radial regions with different exponential warp factors...
Scales and hierarchies in warped compactifications and brane worlds
De Wolfe, O; Wolfe, Oliver De; Giddings, Steven B.
2003-01-01
Warped compactifications with branes provide a new approach to the hierarchy problem and generate a diversity of four-dimensional thresholds. We investigate the relationships between these scales, which fall into two classes. Geometrical scales, such as thresholds for Kaluza-Klein, excited string, and black hole production, are generically determined soley by the spacetime geometry. Dynamical scales, notably the scale of supersymmetry breaking and moduli masses, depend on other details of the model. We illustrate these relationships in a class of solutions of type IIB string theory with imaginary self-dual fluxes. After identifying the geometrical scales and the resulting hierarchy, we determine the gravitino and moduli masses through explicit dimensional reduction, and estimate their value to be near the four-dimensional Planck scale. In the process we obtain expressions for the superpotential and Kahler potential, including the effects of warping. We identify matter living on certain branes to be effectivel...
Smart warping harnesses for active mirrors and stress polishing
Lemared, Sabri; Hugot, Emmanuel; Challita, Zalpha; Schnetler, Hermine; Kroes, Gabby; Marcos, Michel; Costille, Anne; Dohlen, Kjetil; Beuzit, Jean-Luc; Cuby, Jean-Gabriel
2016-07-01
We present two ways to generate or compensate for first order optical aberrations using smart warping harnesses. In these cases, we used the same methodology leading to replace a previous actuation system currently on-sky and to get a freeform mirror intended to a demonstrator. Starting from specifications, a warping harness is designed, followed by a meshing model in the finite elements software. For the two projects, two different ways of astigmatism generation are presented. The first one, on the VLT-SPHERE instrument, with a single actuator, is able to generate a nearly pure astigmatism via a rotating motorization. Two actuators are sufficient to produce the same aberration for the active freeform mirror, main part of the OPTICON-FAME project, in order to use stress-polishing method.
LHC Signatures of Warped-space Vectorlike Quarks
Gopalakrishna, Shrihari; Mitra, Subhadip; Moreau, Gregory
2014-01-01
We study the LHC signatures of TeV scale vectorlike quarks $b'$, $t'$ and $\\chi$ with electromagnetic charges -1/3, 2/3 and 5/3 that appear in many beyond the standard model (BSM) extensions. We consider warped extradimensional models and analyze the phenomenology of such vectorlike quarks that are the custodial partners of third generation quarks. In addition to the usually studied pair-production channels which depend on the strong coupling, we put equal emphasis on single production channels that depend on electroweak couplings and on electroweak symmetry breaking induced mixing effects between the heavy vectorlike quarks and standard model quarks. Although the motivation is from warped models, we present many of our results model-independently.
Multiply-warped product metrics and reduction of Einstein equations
Gholami, F; Haji-Badali, A
2016-01-01
It is shown that for every multidimensional metric in the multiply warped product form $\\bar{M} = K\\times_{f_1} M_1\\times_{f_2}M_2$ with warp functions $f_1$, $f_2$, associated to the submanifolds $M_1$, $M_2$ of dimensions $n_1$, $n_2$ respectively, one can find the corresponding Einstein equations $\\bar{G}_{AB}=-\\bar{\\Lambda}\\bar{g}_{AB}$, with cosmological constant $\\bar{\\Lambda}$, which are reducible to the Einstein equations $G_{\\alpha\\beta} = -\\Lambda_1 g_{\\alpha\\beta}$ and $G_{ij} =-\\Lambda_2 h_{ij}$ on the submanifolds $M_1$, $M_2$, with cosmological constants ${\\Lambda_1}$ and ${\\Lambda_2}$, respectively, where $\\bar{\\Lambda}$, ${\\Lambda_1}$ and ${\\Lambda_2}$ are functions of ${f_1}$, ${f_2}$ and $n_1$, $n_2$.
Damping of Torsional Beam Vibrations by Control of Warping Displacement
DEFF Research Database (Denmark)
Høgsberg, Jan Becker; Hoffmeyer, David; Ejlersen, Christian
2016-01-01
Supplemental damping of torsional beam vibrations is considered by viscous bimoments acting on the axial warping displacement at the beam supports. The concept is illustrated by solving the governing eigenvalue problem for various support configurations with the applied bimoments represented...... as viscous boundary conditions. It is demonstrated that properly calibrated viscous bimoments introduce a significant level of supplemental damping to the targeted vibration mode and that the attainable damping can be accurately estimated from the two undamped problems associated with vanishing and infinite...
Fermion Masses and Mixing in General Warped Extra Dimensional Models
Frank, Mariana; Pourtolami, Nima; Toharia, Manuel
2015-01-01
We analyze fermion masses and mixing in a general warped extra dimensional model, where all the Standard Model (SM) fields, including the Higgs, are allowed to propagate in the bulk. In this context, a slightly broken flavor symmetry imposed universally on all fermion fields, without distinction, can generate the full flavor structure of the SM, including quarks, charged leptons and neutrinos. For quarks and charged leptons, the exponential sensitivity of their wave-functions to small flavor breaking effects yield naturally hierarchical masses and mixing as it is usual in warped models with fermions in the bulk. In the neutrino sector, the exponential wave-function factors can be flavor-blind and thus insensitive to the small flavor symmetry breaking effects, directly linking their masses and mixing angles to the flavor symmetric structure of the 5D neutrino Yukawa couplings. The Higgs must be localized in the bulk and the model is naturally more successful in generalized warped scenarios where the metric bac...
Fermion masses and mixing in general warped extra dimensional models
Frank, Mariana; Hamzaoui, Cherif; Pourtolami, Nima; Toharia, Manuel
2015-06-01
We analyze fermion masses and mixing in a general warped extra dimensional model, where all the Standard Model (SM) fields, including the Higgs, are allowed to propagate in the bulk. In this context, a slightly broken flavor symmetry imposed universally on all fermion fields, without distinction, can generate the full flavor structure of the SM, including quarks, charged leptons and neutrinos. For quarks and charged leptons, the exponential sensitivity of their wave functions to small flavor breaking effects yield hierarchical masses and mixing as it is usual in warped models with fermions in the bulk. In the neutrino sector, the exponential wave-function factors can be flavor blind and thus insensitive to the small flavor symmetry breaking effects, directly linking their masses and mixing angles to the flavor symmetric structure of the five-dimensional neutrino Yukawa couplings. The Higgs must be localized in the bulk and the model is more successful in generalized warped scenarios where the metric background solution is different than five-dimensional anti-de Sitter (AdS5 ). We study these features in two simple frameworks, flavor complimentarity and flavor democracy, which provide specific predictions and correlations between quarks and leptons, testable as more precise data in the neutrino sector becomes available.
Effect of Firing on Cracking and Warping of Clay Beams
Directory of Open Access Journals (Sweden)
Nawab Ali Lakho
2016-04-01
Full Text Available Reinforced baked clay beams may be considered to be a substitute of reinforced cement concrete beams in order to build low cost houses. The baking of these clay beams can pose problems such as cracking and warping. This paper presents the effect of different treatments applied to clay beams during baking to reduce cracking and warping. These clay beams were baked in pottery kiln in which the temperature could not be raised to the extent of fusing of clay beams placed at bottom of firing chamber. As expected, the beams were not baked properly and a number of them got cracked. Then these beams were baked in a commercial Hoffman?s kiln. The beams, in preheating stage, were moistened to full depth due to humidity and moisture of flue gases. As a result, the beams cracked and warped at the time of firing. In order to avoid the beams from being moistened by the moisture of the flue gases, different treatments were opted. Firstly, these beams were covered with plastic sheet, the cracks were reduced to some extent. Secondly, double layer of mud, with a layer of gunny bags between them, was applied. Consequently, a few cracks occurred in the beams. The treatments suggested in this paper can be used for baking of clay beams in Hoffman?s kiln at commercial level
WarpIV: In Situ Visualization and Analysis of Ion Accelerator Simulations.
Rubel, Oliver; Loring, Burlen; Vay, Jean-Luc; Grote, David P; Lehe, Remi; Bulanov, Stepan; Vincenti, Henri; Bethel, E Wes
2016-01-01
The generation of short pulses of ion beams through the interaction of an intense laser with a plasma sheath offers the possibility of compact and cheaper ion sources for many applications--from fast ignition and radiography of dense targets to hadron therapy and injection into conventional accelerators. To enable the efficient analysis of large-scale, high-fidelity particle accelerator simulations using the Warp simulation suite, the authors introduce the Warp In situ Visualization Toolkit (WarpIV). WarpIV integrates state-of-the-art in situ visualization and analysis using VisIt with Warp, supports management and control of complex in situ visualization and analysis workflows, and implements integrated analytics to facilitate query- and feature-based data analytics and efficient large-scale data analysis. WarpIV enables for the first time distributed parallel, in situ visualization of the full simulation data using high-performance compute resources as the data is being generated by Warp. The authors describe the application of WarpIV to study and compare large 2D and 3D ion accelerator simulations, demonstrating significant differences in the acceleration process in 2D and 3D simulations. WarpIV is available to the public via https://bitbucket.org/berkeleylab/warpiv. The Warp In situ Visualization Toolkit (WarpIV) supports large-scale, parallel, in situ visualization and analysis and facilitates query- and feature-based analytics, enabling for the first time high-performance analysis of large-scale, high-fidelity particle accelerator simulations while the data is being generated by the Warp simulation suite. This supplemental material https://extras.computer.org/extra/mcg2016030022s1.pdf provides more details regarding the memory profiling and optimization and the Yee grid recentering optimization results discussed in the main article.
National Aeronautics and Space Administration — In rotorcraft flight dynamics, optimized warping camber/twist change is a potentially enabling technology for improved overall rotorcraft performance. Recent...
Surface states in a 3D topological insulator: The role of hexagonal warping and curvature
Energy Technology Data Exchange (ETDEWEB)
Repin, E. V.; Burmistrov, I. S., E-mail: burmi@itp.ac.ru [Moscow Institute of Physics and Technology (Russian Federation)
2015-09-15
We explore a combined effect of hexagonal warping and a finite effective mass on both the tunneling density of electronic surface states and the structure of Landau levels of 3D topological insulators. We find the increasing warping to transform the square-root van Hove singularity into a logarithmic one. For moderate warping, an additional logarithmic singularity and a jump in the tunneling density of surface states appear. By combining the perturbation theory and the WKB approximation, we calculate the Landau levels in the presence of hexagonal warping. We predict that due to the degeneracy removal, the evolution of Landau levels in the magnetic field is drastically modified.
Stone, Wesley W.; Gilliom, Robert J.
2012-01-01
Watershed Regressions for Pesticides (WARP) models, previously developed for atrazine at the national scale, are improved for application to the United States (U.S.) Corn Belt region by developing region-specific models that include watershed characteristics that are influential in predicting atrazine concentration statistics within the Corn Belt. WARP models for the Corn Belt (WARP-CB) were developed for annual maximum moving-average (14-, 21-, 30-, 60-, and 90-day durations) and annual 95th-percentile atrazine concentrations in streams of the Corn Belt region. The WARP-CB models accounted for 53 to 62% of the variability in the various concentration statistics among the model-development sites. Model predictions were within a factor of 5 of the observed concentration statistic for over 90% of the model-development sites. The WARP-CB residuals and uncertainty are lower than those of the National WARP model for the same sites. Although atrazine-use intensity is the most important explanatory variable in the National WARP models, it is not a significant variable in the WARP-CB models. The WARP-CB models provide improved predictions for Corn Belt streams draining watersheds with atrazine-use intensities of 17 kg/km2 of watershed area or greater.
Beam Dynamics in an Electron Lens with the Warp Particle-in-cell Code
Stancari, Giulio; Redaelli, Stefano
2014-01-01
Electron lenses are a mature technique for beam manipulation in colliders and storage rings. In an electron lens, a pulsed, magnetically confined electron beam with a given current-density profile interacts with the circulating beam to obtain the desired effect. Electron lenses were used in the Fermilab Tevatron collider for beam-beam compensation, for abort-gap clearing, and for halo scraping. They will be used in RHIC at BNL for head-on beam-beam compensation, and their application to the Large Hadron Collider for halo control is under development. At Fermilab, electron lenses will be implemented as lattice elements for nonlinear integrable optics. The design of electron lenses requires tools to calculate the kicks and wakefields experienced by the circulating beam. We use the Warp particle-in-cell code to study generation, transport, and evolution of the electron beam. For the first time, a fully 3-dimensional code is used for this purpose.
Traces of warping subsided tectonic blocks on Miranda, Enceladus, Titan
Kochemasov, G.
2007-08-01
Icy satellites of the outer Solar system have very large range of sizes - from kilometers to thousands of kilometers. Bodies less than 400-500 km across have normally irregular shapes , often presenting simple Plato's polyhedrons woven by standing inertiagravity waves (see an accompanying abstract of Kochemasov). Larger bodies with enhanced gravity normally are rounded off and have globular shapes but far from ideal spheres. This is due to warping action of inertia-gravity waves of various wavelengths origin of which is related to body movements in elliptical keplerian orbits with periodically changing accelerations (alternating accelerations cause periodically changing forces acting upon a body what means oscillations of its spheres in form of standing warping waves). The fundamental wave 1 and its first overtone wave 2 produce ubiquitous tectonic dichotomy - two segmental structure and tectonic sectoring superimposed on this dichotomy. Two kinds of tectonic blocks (segments and sectors) are formed: uplifted (+) and subsided (-). Uplifting means increasing planetary radius of blocks, subsiding - decreasing radius (as a sequence subsiding blocks diminishing their surfaces must be warped, folded, wrinkled; uplifting blocks increasing their surfaces tend to be deeply cracked, fallen apart). To level changing angular momenta of blocks subsided areas are filled with denser material than uplifted ones (one of the best examples is Earth with its oceanic basins filled with dense basalts and uplifted continents built of less dense on average andesitic material). Icy satellites follow the same rule. Their warped surfaces show differing chemistries or structures of constructive materials. Uplifted blocks are normally built with light (by color and density) water ice. Subsided blocks - depressions, "seas', "lakes", coronas - by somewhat denser material differing in color from water ice (very sharply - Iapetus, moderately - Europa, slightly - many saturnian satellites). A very
Performance of resin transfer molded multiaxial warp knit composites
Dexter, H. Benson; Hasko, Gregory H.
1993-01-01
Composite materials that are subjected to complex loads have traditionally been fabricated with multidirectionally oriented prepreg tape materials. Some of the problems associated with this type of construction include low delamination resistance, poor out-of-plane strength, and labor intensive fabrication processes. Textile reinforced composites with through-the-thickness reinforcement have the potential to solve some of these problems. Recently, a relatively new class of noncrimp fabrics designated as multiaxial warp knits have been developed to minimize some of the high cost and damage tolerance concerns. Multiple stacks of warp knit fabrics can be knitted or stitched together to reduce layup labor cost. The through-the-thickness reinforcement can provide significant improvements in damage tolerance and out-of-plane strength. Multilayer knitted/stitched preforms, in conjunction with resin transfer molding (RTM), offer potential for significant cost savings in fabrication of primary aircraft structures. The objectives of this investigation were to conduct RTM processing studies and to characterize the mechanical behavior of composites reinforced with three multiaxial warp knit fabrics. The three fabrics investigated were produced by Hexcel and Milliken in the United States, and Saerbeck in Germany. Two resin systems, British Petroleum E9O5L and 3M PR 500, were characterized for RTM processing. The performance of Hexcel and Milliken quasi-isotropic knitted fabrics are compared to conventional prepreg tape laminates. The performance of the Saerbeck fabric is compared to uniweave wing skin layups being investigated by Douglas Aircraft Company in the NASA Advanced Composites Technology (ACT) program. Tests conducted include tension, open hole tension, compression, open hole compression, and compression after impact. The effects of fabric defects, such as misaligned fibers and gaps between tows, on material performance are also discussed. Estimated material and labor
Pre filtered Dynamic Time Warping for Posteriorgram Based Keyword Search
2017-02-09
retrieval,” IEEE/ACM Transactions on Audio, Speech, and Language Process- ing, vol. 23, no. 9, pp. 1389–1420, 2015. [2] Ciprian Chelba, Timothy J...curate dynamic time warping in linear time and space,” in Proceedings of Mining Temporal and Sequential Data, 2004. [12] Eamonn Keogh and Chotirat Ann...Saraclar, “Lattice indexing for spoken term detection,” IEEE Transactions on Audio, Speech, and Language Processing, vol. 19, no. 8, pp. 2338–2347, 2011
Differential RF MEMS interwoven capacitor immune to residual stress warping
Elshurafa, Amro M.
2012-07-27
A RF MEMS capacitor with an interwoven structure is designed, fabricated in the PolyMUMPS process and tested in an effort to address fabrication challenges usually faced in MEMS processes. The interwoven structure was found to offer several advantages over the typical MEMS parallel-plate design including eliminating the warping caused by residual stress, eliminating the need for etching holes, suppressing stiction, reducing parasitics and providing differential capability. The quality factor of the proposed capacitor was higher than five throughout a 2–10 GHz range and the resonant frequency was in excess of 20 GHz.
Stabilization of moduli in spacetime with nested warping
Arun, Mathew Thomas
2016-01-01
The absence, so far, of any graviton signatures at the LHC imposes severe constraints on the Randall-Sundrum scenario. Although a generalization to higher dimensions with nested warpings has been shown to avoid these constraints, apart from incorporating several other phenomenologically interesting features, moduli stabilization in such models has been an open question. We demonstrate here how both the moduli involved can be stabilized, employing slightly different mechanisms for the two branches of the theory. This also offers a dynamical mechanism to generate and stabilize the UED scale.
Cosmological evolution in a two-brane warped geometry model
Directory of Open Access Journals (Sweden)
Sumit Kumar
2015-07-01
Full Text Available We study an effective 4-dimensional scalar–tensor field theory, originated from an underlying brane–bulk warped geometry, to explore the scenario of inflation. It is shown that the inflaton potential naturally emerges from the radion energy–momentum tensor which in turn results in an inflationary model of the Universe on the visible brane that is consistent with the recent results from the Planck's experiment. The dynamics of modulus stabilization from the inflaton rolling condition is demonstrated. The implications of our results in the context of recent BICEP2 results are also discussed.
Cosmological evolution in a two-brane warped geometry model
Energy Technology Data Exchange (ETDEWEB)
Kumar, Sumit, E-mail: sumit@ctp-jamia.res.in [Center For Theoretical Physics, Jamia Millia Islamia, New Delhi 110025 (India); Sen, Anjan A., E-mail: aasen@jmi.ac.in [Center For Theoretical Physics, Jamia Millia Islamia, New Delhi 110025 (India); SenGupta, Soumitra, E-mail: tpssg@iacs.res.in [Department of Theoretical Physics, Indian Association for the Cultivation of Science, Kolkata 700032 (India)
2015-07-30
We study an effective 4-dimensional scalar–tensor field theory, originated from an underlying brane–bulk warped geometry, to explore the scenario of inflation. It is shown that the inflaton potential naturally emerges from the radion energy–momentum tensor which in turn results in an inflationary model of the Universe on the visible brane that is consistent with the recent results from the Planck's experiment. The dynamics of modulus stabilization from the inflaton rolling condition is demonstrated. The implications of our results in the context of recent BICEP2 results are also discussed.
Light dilatons in warped space: Higgs boson and LHCb anomalies
Megias, Eugenio; Pujolas, Oriol; Quiros, Mariano
2016-01-01
We study the extension of the Standard Model (SM) with a light dilaton in a five dimensional warped model. In particular, we analyze the coupling of the dilaton with the SM matter fields, compare the model predictions with Electroweak Precisions Tests and find the corresponding bounds on the mass of the lightest Kaluza-Klein modes. We also investigate the possibility that the Higgs-like resonance found at the LHC can be a dilaton. Finally, we show that our set-up can also provide an explanation of the anomalies recently observed in $B$-meson decays.
Cosmological evolution in a two-brane warped geometry model
Kumar, Sumit; SenGupta, Soumitra
2014-01-01
We study an effective 4-dimensional scalar-tensor field theory, originated from an underlying brane-bulk warped geometry, to explore the scenario of inflation. It is shown that the inflaton potential naturally emerges from the radion energy-momentum tensor which in turn results into an inflationary model of the Universe on the visible brane that is consistent with the recent results from the Planck's experiment. The dynamics of modulus stabilization from the inflaton rolling condition is demonstrated. The implications of our results in the context of recent BICEP2 results are also discussed.
Secondary Electron Interference from Trigonal Warping in Clean Carbon Nanotubes
Dirnaichner, A.; del Valle, M.; Götz, K. J. G.; Schupp, F. J.; Paradiso, N.; Grifoni, M.; Strunk, Ch.; Hüttel, A. K.
2016-10-01
We investigate Fabry-Perot interference in an ultraclean carbon nanotube resonator. The conductance shows a clear superstructure superimposed onto conventional Fabry-Perot oscillations. A sliding average over the fast oscillations reveals a characteristic slow modulation of the conductance as a function of the gate voltage. We identify the origin of this secondary interference in intervalley and intravalley backscattering processes which involve wave vectors of different magnitude, reflecting the trigonal warping of the Dirac cones. As a consequence, the analysis of the secondary interference pattern allows us to estimate the chiral angle of the carbon nanotube.
750 GeV Diphoton Resonance in Warped Geometries
Hewett, JoAnne L
2016-01-01
We examine the scenario of a warped extra dimension containing bulk SM fields in light of the observed diphoton excess at 750 GeV. We demonstrate that a bulk spin-2 graviton whose action contains localized kinetic brane terms is compatible with the excess, while being consistent with all other constraints. This model contains a single free parameter, the mass of the first gauge Kaluza-Klein excitation. The scale of physics on the IR-brane is found to lie in the range of a ~ few TeV, relevant to the gauge hierarchy.
Generalized virial theorem in warped DGP brane-world
Heydari-Fard, Malihe
2012-01-01
We generalize the virial theorem to the warped DGP brane world scenario and consider its implications on the virail mass. In this theory the four dimensional scalar curvature term is included in the bulk action and the resulting four dimensional effective Einstein equation is augmented with extra terms which can be interpreted as geometrical mass, contributing to the gravitational energy. Estimating the geometrical mass using the observational data, we show that these geometric terms may account for the virial mass discrepancy in clusters of galaxies. Finally, we obtain the radial velocity dispersion of galaxy clusters and show that it is compatible with the radial velocity dispersion profle of such clusters.
Multifunction myoelectric control using multi-dimensional dynamic time warping.
AbdelMaseeh, Meena; Tsu-Wei Chen; Stashuk, Daniel
2014-01-01
Myoelectric control can be used for a variety of applications including powered protheses and different human computer interface systems. The aim of this study is to investigate the formulation of myoelectric control as a multi-class distance-based classification of multidimensional sequences. More specifically, we investigate (1) estimation of multi-muscle activation sequences from multi-channel electromyographic signals in an online manner, and (2) classification using a distance metric based on multi-dimensional dynamic time warping. Subject-specific results across 5 subjects executing 10 different hand movements showed an accuracy of 95% using offline extracted trajectories and an accuracy of 84% using online extracted trajectories.
Orientifolds of Warped Throats from Toric Calabi-Yau Singularities
Retolaza, Ander
2016-01-01
We study the complex deformations of orientifolds of D3-branes at toric CY singularities, using their description in terms of dimer diagrams. We describe orientifold quotients that have fixed lines or fixed points in the dimer, and characterize the possibilities to deform them in terms of the behaviour of zig-zag paths under the orientifold symmetry. The resulting models are holographic duals to warped throats with orientifold planes. Our systematic construction provides a general class of configurations which includes models recently appeared in the context of de Sitter uplift by nilpotent goldstino or dynamical supersymmetry breaking.
LHC Signals of Non-Custodial Warped 5D Models
de Blas, Jorge; Ostdiek, Bryan; de la Puente, Alejandro
2012-01-01
We study the implications at the LHC for a recent class of non-custodial warped extra-dimensional models where the AdS_5 metric is modified near the infrared brane. Such models allow for TeV Kaluza-Klein excitations without conflict with electroweak precision tests. We discuss both the production of electroweak and strong Kaluza-Klein gauge bosons. As we will show, only signals involving the third generation of quarks seem to be feasible in order to probe this scenario.
6D supergravity. Warped solution and gravity mediated supersymmetry breaking
Energy Technology Data Exchange (ETDEWEB)
Luedeling, C.
2006-07-15
We consider compactified six-dimensional gauged supergravity and find the general warped solution with four-dimensional maximal symmetry. Important features of the solution such as the number and position of singularities are determined by a free holomorphic function. Furthermore, in a particular torus compactification we derive the supergravity coupling of brane fields by the Noether procedure and investigate gravity-mediated supersymmetry breaking. The effective Kaehler potential is not sequestered, yet tree level gravity mediation is absent as long as the superpotential is independent of the radius modulus. (orig.)
TWOS - TIME WARP OPERATING SYSTEM, VERSION 2.5.1
Bellenot, S. F.
1994-01-01
The Time Warp Operating System (TWOS) is a special-purpose operating system designed to support parallel discrete-event simulation. TWOS is a complete implementation of the Time Warp mechanism, a distributed protocol for virtual time synchronization based on process rollback and message annihilation. Version 2.5.1 supports simulations and other computations using both virtual time and dynamic load balancing; it does not support general time-sharing or multi-process jobs using conventional message synchronization and communication. The program utilizes the underlying operating system's resources. TWOS runs a single simulation at a time, executing it concurrently on as many processors of a distributed system as are allocated. The simulation needs only to be decomposed into objects (logical processes) that interact through time-stamped messages. TWOS provides transparent synchronization. The user does not have to add any more special logic to aid in synchronization, nor give any synchronization advice, nor even understand much about how the Time Warp mechanism works. The Time Warp Simulator (TWSIM) subdirectory contains a sequential simulation engine that is interface compatible with TWOS. This means that an application designer and programmer who wish to use TWOS can prototype code on TWSIM on a single processor and/or workstation before having to deal with the complexity of working on a distributed system. TWSIM also provides statistics about the application which may be helpful for determining the correctness of an application and for achieving good performance on TWOS. Version 2.5.1 has an updated interface that is not compatible with 2.0. The program's user manual assists the simulation programmer in the design, coding, and implementation of discrete-event simulations running on TWOS. The manual also includes a practical user's guide to the TWOS application benchmark, Colliding Pucks. TWOS supports simulations written in the C programming language. It is designed
Quantization of charges and fluxes in warped Stenzel geometry
Hashimoto, Akikazu
2011-01-01
We examine the quantization of fluxes for the warped Stiefel cone and Stenzel geometries and their orbifolds, and distinguish the roles of three related notions of charge: Page, Maxwell, and brane. The orbifolds admit discrete torsion, and we describe the associated quantum numbers which are consistent with the geometry in its large radius and small radius limits from both the type IIA and the M-theory perspectives. The discrete torsion, measured by a Page charge, is related to the number of fractional branes. We relate the shifts in the Page charges under large gauge transformations to the Hanany-Witten brane creation effect.
Warping and Precession of Accretion Disks in X-Ray Binaries
Begelman, Mitchell C.; Maloney, Philip R.
2001-01-01
This proposal covers research on the radiation-driven warping instability discovered by Pringle. In the first two years of funding under this proposal we concentrated on and essentially completed study of the eigenmodes of the radiation-driven warping instability in the linear regime.
A catalog of warps in spiral and lenticular galaxies in the Southern hemisphere
Sánchez-Saavedra, M L; Guijarro, A; López-Corredoira, M; Castro-Rodriguez, N
2003-01-01
A catalog of optical warps of galaxies is presented. This can be considered complementary to that reported by Sanchez-Saavedra et al., with 42 galaxies in the northern hemisphere, and to that by Reshetnikov & Combes, with 60 optical warps. The limits of the present catalog are: logr25 > 0.60, B_{t} < 14.5, delta(2000) < 0, -2.5 < t < 7. Therefore, lenticular galaxies have also been considered. This catalog lists 150 warped galaxies out of a sample of 276 edge-on galaxies and covers the whole southern hemisphere, except the Avoidance Zone. It is therefore very suitable for statistical studies of warps. It also provides a source guide for detailed particular observations. We confirm the large frequency of warped spirals: nearly all galaxies are warped. The frequency and warp angle do not present important differences for the different types of spirals. However, no lenticular warped galaxy has been found within the specified limits. This finding constitutes an important restriction for theoretica...
The space of virtual solutions to the warped product Einstein equation
He, Chenxu; Wylie, William
2011-01-01
In this paper we introduce a vector space of virtual warping functions that yield Einstein metrics over a fixed base. There is a natural quadratic form on this space and we study how this form interacts with the geometry. We use this structure along with the results in our earlier paper "Warped product rigidity" to show that essentially every warped product Einstein manifold admits a particularly nice warped product structure that we call basic. As applications we give a sharp characterization of when a homogeneous Einstein metric can be a warped product and also generalize a construction of Lauret showing that any algebraic soliton on a general Lie group can be extended to a left invariant Einstein metric.
Coupled flexural-torsional vibration band gap in periodic beam including warping effect
Institute of Scientific and Technical Information of China (English)
Fang Jian-Yu; Yu Dian-Long; Han Xiao-Yun; Cai Li
2009-01-01
The propagation of coupled flexural-torsional vibration in the periodic beam including warping effect is investigated with the transfer matrix theory.The band structures of the periodic beam,both including warping effect and ignoring warping effect,are obtained.The frequency response function of the finite periodic beams is simulated with finite element method,which shows large vibration attenuation in the frequency range of the gap as expected.The effect of warping stiffness on the band structure is studied and it is concluded that substantial error can be produced in high frequency range if the effect is ignored.The result including warping effect agrees quite well with the simulated result.
Stone, Wesley W.; Gilliom, Robert J.
2011-01-01
Watershed Regressions for Pesticides (WARP) models, previously developed for atrazine at the national scale, can be improved for application to the U.S. Corn Belt region by developing region-specific models that include important watershed characteristics that are influential in predicting atrazine concentration statistics within the Corn Belt. WARP models for the Corn Belt (WARP-CB) were developed for predicting annual maximum moving-average (14-, 21-, 30-, 60-, and 90-day durations) and annual 95th-percentile atrazine concentrations in streams of the Corn Belt region. All streams used in development of WARP-CB models drain watersheds with atrazine use intensity greater than 17 kilograms per square kilometer (kg/km2). The WARP-CB models accounted for 53 to 62 percent of the variability in the various concentration statistics among the model-development sites.
Effective fermion couplings in warped 5D Higgsless theories
Bechi, J; De Curtis, S; Dominici, Daniele
2006-01-01
We consider a five dimensional SU(2) gauge theory with fermions in the bulk and with additional SU(2) and U(1) kinetic terms on the branes. The electroweak breaking is obtained by boundary conditions. After deconstruction, fermions in the bulk are eliminated by using their equations of motion. In this way Standard Model fermion mass terms and direct couplings to the internal gauge bosons of the moose are generated. The presence of these new couplings gives a new contribution to the epsilon_3 parameter in addition to the gauge boson term. This allows the possibility of a cancellation between the two contributions, which can be local (site by site) or global. Going back to the continuum, we show that the implementation of local cancellation in any generic warped metric leaves massless fermions. This is due to the presence of one horizon on the infrared brane. However we can require a global cancellation of the new physics contributions to the epsilon_3 parameter. This fixes relations among the warp factor and t...
Suppressing Electroweak Precision Observables in 5D Warped Models
Cabrer, Joan A; Quiros, Mariano
2011-01-01
We elaborate on a recently proposed mechanism to suppress large contributions to the electroweak precision observables in five dimensional (5D) warped models, without the need for an extended 5D gauge sector. The main ingredient is a modification of the AdS metric in the vicinity of the infrared (IR) brane corresponding to a strong deviation from conformality in the IR of the 4D holographic dual. We compute the general low energy effective theory of the 5D warped Standard Model, emphasizing additional IR contributions to the wave function renormalization of the light Higgs mode. We also derive expressions for the S and T parameters as a function of a generic 5D metric and zero-mode wave functions. We give an approximate formula for the mass of the radion that works even for strong deviation from the AdS background. We proceed to work out the details of an explicit model and derive bounds for the first KK masses of the various bulk fields. The radion is the lightest new particle although its mass is already at...
Oblique corrections from less-Higgsless models in warped space
Hatanaka, Hisaki
2015-01-01
The Higgsless model in warped extra dimension is reexamined. Dirichlet boundary conditions on the TeV brane are replaced with Robin boundary conditions which are parameterized by a mass parameter $M$. We calculate the Peskin-Takeuchi precision parameters $S$, $T$ and $U$ at tree level. We find that to satisfy the constraints on the precision parameters at $99 \\%$ [$95 \\%$] confidence level (CL) the first Kaluza-Klein excited $Z$ boson, $Z'$, should be heavier than 5 TeV [8 TeV]. The Magnitude of $M$, which is infinitely large in the original model, should be smaller than 200 GeV (70 GeV) for the curvature of the warped space $R^{-1}=10^{16}$ GeV ($10^{8}$ GeV) at $95\\%$ CL. If the Robin boundary conditions are induced by the mass terms localized on the TeV brane, from the $99\\%$ [$95\\%$] bound we find that the brane mass interactions account for more than $97\\%$ [$99\\%$] of the masses of $Z$ and $W$ bosons. Such a brane mass term is naturally interpreted as a vacuum expectation value of the Higgs scalar field...
Gravitational quantum corrections in warped supersymmetric brane worlds
Gregoire, T; Scrucca, C A; Strumia, A; Trincherini, E
2005-01-01
We study gravitational quantum corrections in supersymmetric theories with warped extra dimensions. We develop for this a superfield formalism for linearized gauged supergravity. We show that the 1-loop effective Kahler potential is a simple functional of the KK spectrum in the presence of generic localized kinetic terms at the two branes. We also present a simple understanding of our results by showing that the leading matter effects are equivalent to suitable displacements of the branes. We then apply this general result to compute the gravity-mediated universal soft mass $m_0^2$ in models where the visible and the hidden sectors are sequestered at the two branes. We find that the contributions coming from radion mediation and brane-to-brane mediation are both negative in the minimal set-up, but the former can become positive if the gravitational kinetic term localized at the hidden brane has a sizeable coefficient. We then compare the features of the two extreme cases of flat and very warped geometry, and ...
Automatic view synthesis by image-domain-warping.
Stefanoski, Nikolce; Wang, Oliver; Lang, Manuel; Greisen, Pierre; Heinzle, Simon; Smolic, Aljosa
2013-09-01
Today, stereoscopic 3D (S3D) cinema is already mainstream, and almost all new display devices for the home support S3D content. S3D distribution infrastructure to the home is already established partly in the form of 3D Blu-ray discs, video on demand services, or television channels. The necessity to wear glasses is, however, often considered as an obstacle, which hinders broader acceptance of this technology in the home. Multiviewautostereoscopic displays enable a glasses free perception of S3D content for several observers simultaneously, and support head motion parallax in a limited range. To support multiviewautostereoscopic displays in an already established S3D distribution infrastructure, a synthesis of new views from S3D video is needed. In this paper, a view synthesis method based on image-domain-warping (IDW) is presented that automatically synthesizes new views directly from S3D video and functions completely. IDW relies on an automatic and robust estimation of sparse disparities and image saliency information, and enforces target disparities in synthesized images using an image warping framework. Two configurations of the view synthesizer in the scope of a transmission and view synthesis framework are analyzed and evaluated. A transmission and view synthesis system that uses IDW is recently submitted to MPEG's call for proposals on 3D video technology, where it is ranked among the four best performing proposals.
On the Formation of Warped Gas Disks in Galaxies
Haan, Sebastian
2014-01-01
We consider the most commonly occurring circumstances which apply to galaxies, namely membership in galaxy groups of about $10^{13}h^{-1} M_\\odot$ total mass, and estimate the accompanying physical conditions of intergalactic medium (IGM) density and the relative galaxy-IGM space velocity. We then investigate the dynamical consequences of such a typical galaxy-IGM interaction on a rotating gaseous disk within the galaxy potential. We find that the rotating outer disk is systematically distorted into a characteristic "warp" morphology, of the type that has been well-documented in the majority of well-studied nearby systems. The distortion is established rapidly, within two rotation periods, and is long-lived, surviving for at least ten. A second consequence of the interaction is the formation of a one arm retrograde spiral wave pattern that propagates in the disk. We suggest that the ubiquity of the warp phenomenon might be used to reconstruct both the IGM density profile and individual member orbits within ga...
Modifications to Holographic entanglement entropy in Warped CFT
Song, Wei; Xu, Jianfei
2016-01-01
In arXiv:1601.02634 it was observed that asymptotic boundary conditions play an important role in the study of holographic entanglement beyond AdS/CFT. In particular, the Ryu-Takayanagi proposal must be modified for Warped AdS3 (WAdS3) with Dirichlet boundary conditions. In this paper, we consider AdS3 and WAdS3 with Dirichlet-Neumann boundary conditions. The conjectured holographic duals are Warped Conformal Field Theories (WCFTs), featuring a Virasoro-Kac-Moody algebra. We provide a holographic calculation of the entanglement entropy and Renyi entropy using AdS3/WCFT and WAdS3/WCFT dualities. Our bulk results are consistent with the WCFT results derived by Castro-Hofman-Iqbal using the Rindler method. Comparing with arXiv:1601.02634, we explicitly show that the holographic entanglement entropy is indeed affected by boundary conditions. Both results differs from the Ryu-Takayanagi proposal, indicating new relations between spacetime geometry and quantum entanglement for holographic dualities beyond AdS/CFT.
Time warp operating system version 2.7 internals manual
1992-01-01
The Time Warp Operating System (TWOS) is an implementation of the Time Warp synchronization method proposed by David Jefferson. In addition, it serves as an actual platform for running discrete event simulations. The code comprising TWOS can be divided into several different sections. TWOS typically relies on an existing operating system to furnish some very basic services. This existing operating system is referred to as the Base OS. The existing operating system varies depending on the hardware TWOS is running on. It is Unix on the Sun workstations, Chrysalis or Mach on the Butterfly, and Mercury on the Mark 3 Hypercube. The base OS could be an entirely new operating system, written to meet the special needs of TWOS, but, to this point, existing systems have been used instead. The base OS's used for TWOS on various platforms are not discussed in detail in this manual, as they are well covered in their own manuals. Appendix G discusses the interface between one such OS, Mach, and TWOS.
Stone, Wesley W.; Crawford, Charles G.; Gilliom, Robert J.
2013-01-01
Watershed Regressions for Pesticides for multiple pesticides (WARP-MP) are statistical models developed to predict concentration statistics for a wide range of pesticides in unmonitored streams. The WARP-MP models use the national atrazine WARP models in conjunction with an adjustment factor for each additional pesticide. The WARP-MP models perform best for pesticides with application timing and methods similar to those used with atrazine. For other pesticides, WARP-MP models tend to overpredict concentration statistics for the model development sites. For WARP and WARP-MP, the less-than-ideal sampling frequency for the model development sites leads to underestimation of the shorter-duration concentration; hence, the WARP models tend to underpredict 4- and 21-d maximum moving-average concentrations, with median errors ranging from 9 to 38% As a result of this sampling bias, pesticides that performed well with the model development sites are expected to have predictions that are biased low for these shorter-duration concentration statistics. The overprediction by WARP-MP apparent for some of the pesticides is variably offset by underestimation of the model development concentration statistics. Of the 112 pesticides used in the WARP-MP application to stream segments nationwide, 25 were predicted to have concentration statistics with a 50% or greater probability of exceeding one or more aquatic life benchmarks in one or more stream segments. Geographically, many of the modeled streams in the Corn Belt Region were predicted to have one or more pesticides that exceeded an aquatic life benchmark during 2009, indicating the potential vulnerability of streams in this region.
Mikesell, T. Dylan; Malcolm, Alison E.; Yang, Di; Haney, Matthew M.
2015-01-01
Time-shift estimation between arrivals in two seismic traces before and after a velocity perturbation is a crucial step in many seismic methods. The accuracy of the estimated velocity perturbation location and amplitude depend on this time shift. Windowed cross correlation and trace stretching are two techniques commonly used to estimate local time shifts in seismic signals. In the work presented here, we implement Dynamic Time Warping (DTW) to estimate the warping function – a vector of local time shifts that globally minimizes the misfit between two seismic traces. We illustrate the differences of all three methods compared to one another using acoustic numerical experiments. We show that DTW is comparable to or better than the other two methods when the velocity perturbation is homogeneous and the signal-to-noise ratio is high. When the signal-to-noise ratio is low, we find that DTW and windowed cross correlation are more accurate than the stretching method. Finally, we show that the DTW algorithm has better time resolution when identifying small differences in the seismic traces for a model with an isolated velocity perturbation. These results impact current methods that utilize not only time shifts between (multiply) scattered waves, but also amplitude and decoherence measurements. DTW is a new tool that may find new applications in seismology and other geophysical methods (e.g., as a waveform inversion misfit function).
Baumann, Matthias; Ozdogan, Mutlu; Richardson, Andrew D.; Radeloff, Volker C.
2017-02-01
Green-leaf phenology describes the development of vegetation throughout a growing season and greatly affects the interaction between climate and the biosphere. Remote sensing is a valuable tool to characterize phenology over large areas but doing at fine- to medium resolution (e.g., with Landsat data) is difficult because of low numbers of cloud-free images in a single year. One way to overcome data availability limitations is to merge multi-year imagery into one time series, but this requires accounting for phenological differences among years. Here we present a new approach that employed a time series of a MODIS vegetation index data to quantify interannual differences in phenology, and Dynamic Time Warping (DTW) to re-align multi-year Landsat images to a common phenology that eliminates year-to-year phenological differences. This allowed us to estimate annual phenology curves from Landsat between 2002 and 2012 from which we extracted key phenological dates in a Monte-Carlo simulation design, including green-up (GU), start-of-season (SoS), maturity (Mat), senescence (Sen), end-of-season (EoS) and dormancy (Dorm). We tested our approach in eight locations across the United States that represented forests of different types and without signs of recent forest disturbance. We compared Landsat-based phenological transition dates to those derived from MODIS and ground-based camera data from the PhenoCam-network. The Landsat and MODIS comparison showed strong agreement. Dates of green-up, start-of-season and maturity were highly correlated (r 0.86-0.95), as were senescence and end-of-season dates (r > 0.85) and dormancy (r > 0.75). Agreement between the Landsat and PhenoCam was generally lower, but correlation coefficients still exceeded 0.8 for all dates. In addition, because of the high data density in the new Landsat time series, the confidence intervals of the estimated keydates were substantially lower than in case of MODIS and PhenoCam. Our study thus suggests
Directory of Open Access Journals (Sweden)
Sophie Deckx
Full Text Available Von Willebrand A domain Related Protein (WARP, is a recently identified extracellular matrix protein. Based upon its involvement in matrix biology and its expression in the heart, we hypothesized that WARP regulates cardiac remodeling processes in the post-infarct healing process.In the mouse model of myocardial infarction (MI, WARP expression increased in the infarcted area 3-days post-MI. In the healthy myocardium WARP localized with perlecan in the basement membrane, which was disrupted upon injury. In vitro studies showed high expression of WARP by cardiac fibroblasts, which further increases upon TGFβ stimulation. Furthermore, WARP expression correlated with aSMA and COL1 expression, markers of fibroblast to myofibroblast transition, in vivo and in vitro. Finally, WARP knockdown in vitro affected extra- and intracellular basic fibroblast growth factor production in myofibroblasts. To investigate the function for WARP in infarction healing, we performed an MI study in WARP knockout (KO mice backcrossed more than 10 times on an Australian C57Bl/6-J background and bred in-house, and compared to wild type (WT mice of the same C57Bl/6-J strain but of commercial European origin. WARP KO mice showed no mortality after MI, whereas 40% of the WT mice died due to cardiac rupture. However, when WARP KO mice were backcrossed on the European C57Bl/6-J background and bred heterozygous in-house, the previously seen protective effect in the WARP KO mice after MI was lost. Importantly, comparison of the cardiac response post-MI in WT mice bred heterozygous in-house versus commercially purchased WT mice revealed differences in cardiac rupture.These data demonstrate a redundant role for WARP in the wound healing process after MI but demonstrate that the continental/breeding/housing origin of mice of the same C57Bl6-J strain is critical in determining the susceptibility to cardiac rupture and stress the importance of using the correct littermate controls.
Nonlinear Gravitational Waves as Dark Energy in Warped Spacetimes
Directory of Open Access Journals (Sweden)
Reinoud Jan Slagter
2017-02-01
Full Text Available We find an azimuthal-angle dependent approximate wave like solution to second order on a warped five-dimensional manifold with a self-gravitating U(1 scalar gauge field (cosmic string on the brane using the multiple-scale method. The spectrum of the several orders of approximation show maxima of the energy distribution dependent on the azimuthal-angle and the winding numbers of the subsequent orders of the scalar field. This breakup of the quantized flux quanta does not lead to instability of the asymptotic wavelike solution due to the suppression of the n-dependency in the energy momentum tensor components by the warp factor. This effect is triggered by the contribution of the five dimensional Weyl tensor on the brane. This contribution can be understood as dark energy and can trigger the self-acceleration of the universe without the need of a cosmological constant. There is a striking relation between the symmetry breaking of the Higgs field described by the winding number and the SO(2 breaking of the axially symmetric configuration into a discrete subgroup of rotations of about 180 ∘ . The discrete sequence of non-axially symmetric deviations, cancelled by the emission of gravitational waves in order to restore the SO(2 symmetry, triggers the pressure T z z for discrete values of the azimuthal-angle. There could be a possible relation between the recently discovered angle-preferences of polarization axes of quasars on large scales and our theoretical predicted angle-dependency and this could be evidence for the existence of cosmic strings. Careful comparison of this spectrum of extremal values of the first and second order φ-dependency and the distribution of the alignment of the quasar polarizations is necessary. This can be accomplished when more observational data become available. It turns out that, for late time, the vacuum 5D spacetime is conformally invariant if the warp factor fulfils the equation of a vibrating
Applications of warped geometries: From cosmology to cold atoms
Brown, C. M.
This thesis describes several interrelated projects furthering the study of branes on warped geometries in string theory. First, we consider the non-perturbative interaction between D3 and D7 branes which stabilizes the overall volume in braneworld compactification scenarios. This interaction might offer stable nonsupersymmetric vacua which would naturally break supersymmetry if occupied by D3 branes. We derive the equations for the nonsupersymmetric vacua of the D3-brane and analyze them in the case of two particular 7-brane embeddings at the bottom of the warped deformed conifold. These geometries have negative dark energy. Stability of these models is possible but not generic. Further, we reevaluate brane/flux annihilation in a warped throat with one stabilized Kahler modulus. We find that depending on the relative size of various fluxes three things can occur: the decay process proceeds unhindered, the D3-branes are forbidden to decay classically, or the entire space decompactifies. Additionally, we show that the Kahler modulus receives a contribution from the collective 3-brane tension allowing significant changes in the compactified volume during the transition. Next, furthering the effort to describe cold atoms using AdS/CFT, we construct charged asymptotically Schrodinger black hole solutions of IIB supergravity. We begin by obtaining a closed-form expression for the null Melvin twist of many type IIB backgrounds and identify the resulting five-dimensional effective action. We use these results to demonstrate that the near-horizon physics and thermodynamics of asymptotically Schrodinger black holes obtained in this way are essentially inherited from their AdS progenitors, and verify that they admit zero-temperature extremal limits with AdS2 near-horizon geometries. Finally, in an effort to understand rotating nonrelativistic systems we use the null Melvin twist technology on a charged rotating AdS black hole and discover a type of Godel space-time. We
Energy Technology Data Exchange (ETDEWEB)
Gullberg, Grant T; VERESS , ALEXANDER I.; WEISS, JEFFREY A.; HUESMAN, RONALD H.; REUTTER, BRYAN W.; TAYLOR , SCOTT E.; SITEK , AREK; FENG, BING; YANG , YONGFENG; GULLBERG, GRANT T.
2008-04-04
The objective of this research was to assess applicability of a technique known as hyperelastic warping for the measurement of local strains in the left ventricle (LV) directly from microPET image data sets. The technique uses differences in image intensities between template (reference) and target (loaded) image data sets to generate a body force that deforms a finite element (FE) representation of the template so that it registers with the target images. For validation, the template image was defined as the end-systolic microPET image data set from a Wistar Kyoto (WKY) rat. The target image was created by mapping the template image using the deformation results obtained from a FE model of diastolic filling. Regression analysis revealed highly significant correlations between the simulated forward FE solution and image derived warping predictions for fiber stretch (R2 = 0.96), circumferential strain (R2 = 0.96), radial strain (R2 = 0.93), and longitudinal strain (R2 = 0.76) (p<0.001for all cases). The technology was applied to microPET image data of two spontaneously hypertensive rats (SHR) and a WKY control. Regional analysis revealed that, the lateral freewall in the SHR subjects showed the greatest deformation compared with the other wall segments. This work indicates that warping can accurately predict the strain distributions during diastole from the analysis of microPET data sets.
Reflection-less device allows electromagnetic warp drive
Ochiai, T
2010-01-01
One of the striking properties of artificially structured materials is the negative refraction, an optical feature that known natural materials do not exhibit. Here, we propose a simple design, composed of two parallel layers of materials with different refraction indices $n_1=-n_2$, that constructs perfect reflection-less devices. The electromagnetic waves can tunnel from one layer to the other, a feature that resembles a truncation of the physical space leading to an electromagnetic warp drive. Since the refractive indices do not require any large values, this method demonstrates for the first time the practical feasibility of guiding electromagnetic fields in complete absence of reflection phenomena and without degradation of transmission efficiency at all.
PRESENTATION OF AN ARCHITECTURAL OBJECT DESIGNED BY WARPED SURFACES
Directory of Open Access Journals (Sweden)
VELJKOVIĆ Milica
2015-06-01
Full Text Available Due to the importance of good functional solutions and aesthetic appearance of an object, modeling in architecture is the subject of this study. Application of more modern materials in architecture allows us to perform various geometric surfaces in the production of facade and roof structures. With such complex objects, it is necessary to create detailed three-dimensional models, using some of the modern software package for modeling. This paper provides an example of creating a 3D model of a modern building in whose exterior we can recognize nondevelopmental (becoming warped line-generated surfaces, primarily cylindroids and conoids. The entire process of modeling and presenting an object using augmented reality was carried out using the modern software package for visualization in architecture.
Signals of Warped Extra Dimensions at the LHC
Osland, P; Tsytrinov, A V; Paver, N
2010-01-01
We discuss the signatures of the spin-2 graviton excitations predicted by the Randall-Sundrum model with one warped extra dimension, in dilepton and diphoton production at LHC. By using a specific angular analysis, we assess the ranges in mass and coupling constant where such gravitons can be discriminated against competitor spin-1 and spin-0 objects, that potentially could manifest themselves in these processes with the same mass and rate of events. Depending on the value of the coupling constant to quarks and leptons, the numerical results indicate graviton identification mass ranges up to 1.1-2.4 TeV and 1.6-3.2 TeV for LHC nominal energy of 14 TeV and time-integrated luminosity of 10 and 100~${\\rm fb}^{-1}$, respectively.
Stress-warping relation in thin film coated wafers
Schicker, J.; Khan, W. A.; Arnold, T.; Hirschl, C.
2017-02-01
A misfit strain or stress in a thin layer on the surface of a wafer lets the composite disk warp. When the wafer is thin and large, the Stoney estimation of the film stress as function of the curvature yields large errors. We present a nonlinear analytical model that describes the relationship between warpage and film stress on an anisotropic wafer, and give evidence for its suitability for large thin wafers by a comparison to finite element results. Finally, we show the confidence limit of the Stoney estimation and the benefit by the nonlinear model. For thin coatings, it can be succesfully used even without knowledge of the film properties, which was the main advantage of the Stoney estimation.
Warped 5D Standard Model Consistent with EWPT
Cabrer, Joan A; Quiros, Mariano
2011-01-01
For a 5D Standard Model propagating in an AdS background with an IR localized Higgs, compatibility of bulk KK gauge modes with EWPT yields a phenomenologically unappealing KK spectrum (m > 12.5 TeV) and leads to a "little hierarchy problem". For a bulk Higgs the solution to the hierarchy problem reduces the previous bound only by sqrt(3). As a way out, models with an enhanced bulk gauge symmetry SU(2)_R x U(1)_(B-L) were proposed. In this note we describe a much simpler (5D Standard) Model, where introduction of an enlarged gauge symmetry is no longer required. It is based on a warped gravitational background which departs from AdS at the IR brane and a bulk propagating Higgs. The model is consistent with EWPT for a range of KK masses within the LHC reach.
Apsidal precession, disc breaking and viscosity in warped discs
Nealon, Rebecca; Price, Daniel J; King, Andrew
2015-01-01
We demonstrate the importance of general relativistic apsidal precession in warped black hole accretion discs by comparing three - dimensional smoothed particle hydrodynamic simulations in which this effect is first neglected, and then included. If apsidal precession is neglected, we confirm the results of an earlier magnetohydrodynamic simulation which made this assumption, showing that at least in this case the $\\alpha$ viscosity model produces very similar results to those of simulations where angular momentum transport is due to the magnetorotational instability. Including apsidal precession significantly changes the predicted disc evolution. For moderately inclined discs thick enough that tilt is transported by bending waves, we find a disc tilt which is nonzero at the inner disc edge and oscillates with radius, consistent with published analytic results. For larger inclinations we find disc breaking.
Higgs boson production and decay in 5D warped models
Frank, Mariana; Pourtolami, Nima; Toharia, Manuel
2016-03-01
We calculate the production and decay rates of the Higgs boson at the LHC in the context of general five-dimensional warped scenarios with a spacetime background modified from the usual AdS5 , with Standard Model (SM) fields propagating in the bulk. We extend previous work by considering the full flavor structure of the SM, and thus including all possible flavor effects coming from mixings with heavy fermions. We proceed in three different ways, first by only including two complete Kaluza-Klein (KK) levels (15 ×15 fermion mass matrices), then including three complete KK levels (21 ×21 fermion mass matrices) and finally we compare with the effect of including the infinite (full) KK towers. We present numerical results for the Higgs production cross section via gluon fusion and Higgs decay branching fractions in both the modified metric scenario and in the usual Randall-Sundrum metric scenario.
A Higgs in the Warped Bulk and LHC signals
Mahmoudi, F; Manglani, N; Sridhar, K
2016-01-01
Warped models with the Higgs in the bulk can generate light Kaluza-Klein (KK) Higgs modes consistent with the electroweak precision analysis. The first KK mode of the Higgs (h_{1}) could lie in the 1-2 TeV range in the models with a bulk custodial symmetry. We find that the h_{1} is gaugephobic and decays dominantly into a t\\bar{t} pair. We also discuss the search strategy for h_{1} decaying to t\\bar{t} at the Large Hadron Collider. We used substructure tools to suppress the large QCD background associated with this channel. We find that h_{1} can be probed at the LHC run-2 with an integrated luminosity of 300 fb^{-1}.
Warped extra dimension and inclined events at Pierre Auger Observatory
Kisselev, A V
2016-01-01
The generalized solution for the warp factor of the Randall-Sundrum metric is presented which is symmetric with respect to both branes and explicitly periodic in extra variable. Given that the curvature of the 5-dimensional space-time is small, the expected rate of neutrino-induced inclined events at the Surface Detector of the Pierre Auger Observatory is calculated. Both the "downward-going" (DG) and "Earth-skimming" (ES) neutrinos are considered. By comparing the expected event rate with the recent Auger data on searching for neutrino candidates, the lower bound on the fundamental gravity scale M_5 is obtained. The ratio of the number of the ES air showers to the number of the DG showers is estimated as a function of M_5.
Facility Deployment Decisions through Warp Optimizaton of Regressed Gaussian Processes
Scopatz, Anthony
2015-01-01
A method for quickly determining deployment schedules that meet a given fuel cycle demand is presented here. This algorithm is fast enough to perform in situ within low-fidelity fuel cycle simulators. It uses Gaussian process regression models to predict the production curve as a function of time and the number of deployed facilities. Each of these predictions is measured against the demand curve using the dynamic time warping distance. The minimum distance deployment schedule is evaluated in a full fuel cycle simulation, whose generated production curve then informs the model on the next optimization iteration. The method converges within five to ten iterations to a distance that is less than one percent of the total deployable production. A representative once-through fuel cycle is used to demonstrate the methodology for reactor deployment.
Near-horizon geometry and warped conformal symmetry
Energy Technology Data Exchange (ETDEWEB)
Afshar, Hamid [Van Swinderen Institute for Particle Physics and Gravity, University of Groningen,Nijenborgh 4, 9747 AG Groningen (Netherlands); School of Physics, Institute for Research in Fundamental Sciences (IPM),P.O.Box 19395-5531, Tehran (Iran, Islamic Republic of); Detournay, Stéphane [Physique Théorique et Mathématique, Université Libre de Bruxelles andInternational Solvay Institutes,Campus Plaine C.P. 231, B-1050 Bruxelles (Belgium); Grumiller, Daniel [Institute for Theoretical Physics, TU Wien,Wiedner Hauptstrasse 8-10/136, A-1040 Vienna (Austria); Oblak, Blagoje [Physique Théorique et Mathématique, Université Libre de Bruxelles andInternational Solvay Institutes,Campus Plaine C.P. 231, B-1050 Bruxelles (Belgium); DAMTP, Centre for Mathematical Sciences, University of Cambridge,Wilberforce Road, Cambridge CB3 0WA (United Kingdom)
2016-03-29
We provide boundary conditions for three-dimensional gravity including boosted Rindler spacetimes, representing the near-horizon geometry of non-extremal black holes or flat space cosmologies. These boundary conditions force us to make some unusual choices, like integrating the canonical boundary currents over retarded time and periodically identifying the latter. The asymptotic symmetry algebra turns out to be a Witt algebra plus a twisted u(1) current algebra with vanishing level, corresponding to a twisted warped CFT that is qualitatively different from the ones studied so far in the literature. We show that this symmetry algebra is related to BMS by a twisted Sugawara construction and exhibit relevant features of our theory, including matching micro- and macroscopic calculations of the entropy of zero-mode solutions. We confirm this match in a generalization to boosted Rindler-AdS. Finally, we show how Rindler entropy emerges in a suitable limit.
Canizares, Claude
2011-09-01
We propose multiple HETG observations of the X-ray pulsar, SMC X-1. We will search for spectral signatures associated with radiatively driven winds, which may be responsible for driving a precessing warp, and hence the long term variability. We will study the X-ray heating of the accretion disk atmosphere. We expect the observations to be carried out over several different orbital and super-orbital phases, allowing us to search for spectral differences among these phases. These observations will be enhanced by our contemporaneous Suzaku observation, which will have one CCD run in timing mode to study the pulsar pulse profile. This will be the first, high resolution spectroscopic observations of this important system that will extend beyond 2 keV.
General solution for the warp function in the RS scenario
Kisselev, A V
2014-01-01
The five-dimensional space-time, with non-factorizable geometry and fifth dimension y being an orbifold S^1/Z_2, is studied. In such a scenario, originally suggested by Randall and Sundrum, there exist two branes at fixed points of the orbifold, and the four-dimensional metric is multiplied by a warp factor exp[sigma(y)]. In the present paper, the new aesthetic solution sigma(y) of the Einstein-Hilbert equations is presented which has the orbifold symmetry y -> - y and reproduces jumps of its derivative on both branes. It is also symmetric with respect to an interchange of two branes. The function sigma(y) is determined by the Einstein-Hilbert equations up to a constant, that results in physically diverse schemes.
Lectures on Warped Compactifications and Stringy Brane Constructions
Energy Technology Data Exchange (ETDEWEB)
Kachru, Shamit
2001-07-26
In these lectures, two different aspects of brane world scenarios in 5d gravity or string theory are discussed. In the first two lectures, work on how warped compactifications of 5d gravity theories can change the guise of the hierarchy problem and the cosmological constant problem is reviewed, and a discussion of several issues which remain unclear in this context is provided. In the next two lectures, microscopic constructions in string theory which involve D-branes wrapped on cycles of Calabi-Yau manifolds are described. The focus is on computing the superpotential in the brane worldvolume field theory. Such calculations may be a necessary step towards understanding e.g. supersymmetry breaking and moduli stabilization in stringy realizations of such scenarios, and are of intrinsic interest as probes of the quantum geometry of the Calabi-Yau space.
SPACE WARPS - I. Crowdsourcing the discovery of gravitational lenses
Marshall, Philip J.; Verma, Aprajita; More, Anupreeta; Davis, Christopher P.; More, Surhud; Kapadia, Amit; Parrish, Michael; Snyder, Chris; Wilcox, Julianne; Baeten, Elisabeth; Macmillan, Christine; Cornen, Claude; Baumer, Michael; Simpson, Edwin; Lintott, Chris J.; Miller, David; Paget, Edward; Simpson, Robert; Smith, Arfon M.; Küng, Rafael; Saha, Prasenjit; Collett, Thomas E.
2016-01-01
We describe SPACE WARPS, a novel gravitational lens discovery service that yields samples of high purity and completeness through crowdsourced visual inspection. Carefully produced colour composite images are displayed to volunteers via a web-based classification interface, which records their estimates of the positions of candidate lensed features. Images of simulated lenses, as well as real images which lack lenses, are inserted into the image stream at random intervals; this training set is used to give the volunteers instantaneous feedback on their performance, as well as to calibrate a model of the system that provides dynamical updates to the probability that a classified image contains a lens. Low-probability systems are retired from the site periodically, concentrating the sample towards a set of lens candidates. Having divided 160 deg2 of Canada-France-Hawaii Telescope Legacy Survey imaging into some 430 000 overlapping 82 by 82 arcsec tiles and displaying them on the site, we were joined by around 37 000 volunteers who contributed 11 million image classifications over the course of eight months. This stage 1 search reduced the sample to 3381 images containing candidates; these were then refined in stage 2 to yield a sample that we expect to be over 90 per cent complete and 30 per cent pure, based on our analysis of the volunteers performance on training images. We comment on the scalability of the SPACE WARPS system to the wide field survey era, based on our projection that searches of 105 images could be performed by a crowd of 105 volunteers in 6 d.
Anomalous gauge couplings from composite Higgs and warped extra dimensions
Energy Technology Data Exchange (ETDEWEB)
Fichet, Sylvain [International Institute of Physics, UFRN,Av. Odilon Gomes de Lima, 1722, Capim Macio, 59078-400, Natal-RN (Brazil); Gersdorff, Gero von [ICTP South American Institute for Fundamental Research,Instituto de Fisica Teorica, Sao Paulo State University (Brazil)
2014-03-24
We examine trilinear and quartic anomalous gauge couplings (AGCs) generated in composite Higgs models and models with warped extra dimensions. We first revisit the SU(2){sub L}×U(1){sub Y} effective Lagrangian and derive the charged and two-photon neutral AGCs. We derive the general perturbative contributions to the pure field-strength operators from spin 0, (1/2), 1 resonances by means of the heat kernel method. In the composite Higgs framework, we derive the pattern of expected deviations from typical SO(N) embeddings of the light composite top partner. We then study a generic warped extra dimension framework with AdS{sub 5} background, recasting in few parameters the features of models relevant for AGCs. We also present a detailed study of the latest bounds from electroweak and Higgs precision observables, with and without brane kinetic terms. For vanishing brane kinetic terms, we find that the S and T parameters exclude KK gauge modes of the RS custodial [non-custodial] scenario below 7.7 [14.7] TeV, for a brane Higgs and below 6.6 [8.1] TeV for a Pseudo Nambu-Goldstone Higgs, at 95% CL. These constraints can be relaxed in presence of brane kinetic terms. The leading AGCs are probing the KK gravitons and the KK modes of bulk gauge fields in parts of the parameter space. In these scenarios, the future CMS and ATLAS forward proton detectors could be sensitive to the effect of KK gravitons in the multi-TeV mass range.
Various Types of Five Dimensional Warp Factor and Effective Planck Scale
Ito, M
2002-01-01
Based on the assumption that the warp factor of four dimensional spacetime and the one of fifth dimension are tied through a parameter $\\alpha$, we consider five dimensional gravity with a 3-brane coupled to a bulk scalar field. For arbitrary value of $\\alpha$, the form of the warp factor is implicitly determined by hypergeometric function. Concretely, we show that the warp factor becomes explicit form for appropriate value of $\\alpha$, and study the relation between four dimensional effective Planck scale and the brane tension. This setup allows the possibility of extending the diversity of brane world.
Entropy of Warped Taub-NUT AdS Black String via the Brick Wall Method
Lee, Chong Oh
2014-01-01
When we consider five-dimensional warped Taub-NUT AdS black string with minimally coupled massive scalar field, we calculate an entropy by using the brick wall method. In extremely light effective mass, we find the entropy is proportional to an extra dimension wave number as well as quadratically divergent in a cutoff parameter. After taking zero NUT charge, we find the entropy of warped (AdS) Schwartzshield black hole string has a similar properties in as warped Taub-NUT AdS black string.
Warp Breaks Detection in Jacquard Weaving Using MEMS: Effect of Weave on Break Signals
Directory of Open Access Journals (Sweden)
Jin H Lee, Ph.D.
2008-03-01
Full Text Available This paper reports a study to detect warp breaks in terms of weave structure using MEMS accelerometer based detection system. The system is briefly described. The output signals of MEMS sensors, which were mounted on harness cords of a Jacquard machine, at the moment of warp yarn break and after the break for a broad range of basic weaves were acquired during weaving. The weaves investigated are commonly used in Jacquard weaving to form patterns. The strength of the MEMS output acceleration signals was analyzed in time domain. The results show that the system is capable of detecting warp yarn breaks for the broad range of weaves studied.
Geometric finiteness, holography and quasinormal modes for the warped AdS{sub 3} black hole
Energy Technology Data Exchange (ETDEWEB)
Gupta, Kumar S [Theory Division, Saha Institute of Nuclear Physics, 1/AF Bidhannagar, Calcutta 700064 (India); Harikumar, E; Sivakumar, M [School of Physics, University of Hyderabad, Hyderabad 500046 (India); Sen, Siddhartha, E-mail: kumars.gupta@saha.ac.i, E-mail: harisp@uohyd.ernet.i, E-mail: sen@maths.ucd.i, E-mail: mssp@uohyd.ernet.i [School of Mathematical Sciences, UCD, Belfield, Dublin 4 (Ireland)
2010-08-21
We show that there exists a precise kinematical notion of holography for the Euclidean warped AdS{sub 3} black hole. This follows from the fact that the Euclidean warped AdS{sub 3} black hole spacetime is a geometrically finite hyperbolic manifold. For such manifolds a theorem of Sullivan provides a one-to-one correspondence between the hyperbolic structure in the bulk and the conformal structure of its boundary. Using this theorem we obtain the holographic quasinormal modes for the warped AdS{sub 3} black hole.
Geometric Finiteness, Holography and Quasinormal Modes for the Warped AdS_3 Black Hole
Gupta, Kumar S; Sen, Siddhartha; Sivakumar, M
2009-01-01
We show that there exists a precise kinematical notion of holography for the Euclidean warped $AdS_3$ black hole. This follows from the fact that the Euclidean warped $AdS_3$ black hole spacetime is a geometrically finite hyperbolic manifold. For such manifolds a theorem of Sullivan provides a one-to-one correspondence between the hyperbolic structure in the bulk and the conformal structure of its boundary. Using this theorem we obtain the holographic quasinormal modes for the warped $AdS_3$ black hole.
ANALYSIS OF WARP TENSION DURING WEAVING FABRIC WITH VARIABLE WEFT DENSITY
Directory of Open Access Journals (Sweden)
Yıldıray TURHAN
2004-03-01
Full Text Available In this study, warp tension change has been studied by changing weft density from a lower to a higher value in a weaving machine with electronic take up and electronic let off motions. For this purpose firstly, warp tension and cloth fell distance were measured at certain intervals from the beginning of weaving with a new weft density. Secondly, the length of fabric woven until the cloth fell reached its steady state value was determined. Finally, the warp tension measured until the steady state cloth fell values was analysed.
Boyer, K. L.; Wuescher, D. M.; Sarkar, S.
1991-01-01
Dynamic edge warping (DEW), a technique for recovering reasonably accurate disparity maps from uncalibrated stereo image pairs, is presented. No precise knowledge of the epipolar camera geometry is assumed. The technique is embedded in a system including structural stereopsis on the front end and robust estimation in digital photogrammetry on the other for the purpose of self-calibrating stereo image pairs. Once the relative camera orientation is known, the epipolar geometry is computed and the system can use this information to refine its representation of the object space. Such a system will find application in the autonomous extraction of terrain maps from stereo aerial photographs, for which camera position and orientation are unknown a priori, and for online autonomous calibration maintenance for robotic vision applications, in which the cameras are subject to vibration and other physical disturbances after calibration. This work thus forms a component of an intelligent system that begins with a pair of images and, having only vague knowledge of the conditions under which they were acquired, produces an accurate, dense, relative depth map. The resulting disparity map can also be used directly in some high-level applications involving qualitative scene analysis, spatial reasoning, and perceptual organization of the object space. The system as a whole substitutes high-level information and constraints for precise geometric knowledge in driving and constraining the early correspondence process.
From Wormholes to the Warp Drive: Using theoretical physics to place ultimate bounds on technology
Hiscock, William A.
2002-01-01
The serious study of such science fiction staples as wormholes, time travel, and the warp drive, as a means of understanding and constraining possible realistic solutions within General Relativity is reviewed.
Loredo, Alexandre
2013-01-01
A multilayered plate theory which uses transverse shear warping functions issued from three-dimensional elasticity is presented. Two methods to obtain these transverse shear warping functions are detailed. The warping functions are issued from the variations of transverse shear stresses computed at special location points for a simply supported bending problem. The first method considers an exact 3D solution of the problem. The second method uses the solution provided by the model itself: the transverse shear stresses are computed by the integration of equilibrium equations. Hence, an iterative process is applied, the model being updated with the new warping functions, and so on. These two models are compared to other models and to analytical solutions for the bending of simply supported plates. Four different laminates and a sandwich are considered, length-to-thickness values varying from 2 to 100. An additional analytical solution that simulates the behavior of laminates under the plane stress hypothesis - ...
A multilayered plate theory with transverse shear and normal warping functions
Loredo, A
2014-01-01
A multilayered plate theory which takes into account transverse shear and normal stretching is presented. The theory is based on a seven-unknowns kinematic field with five warping functions. Four warping functions are related to the transverse shear behaviour, the fifth is related to the normal stretching. The warping functions are issued from exact three-dimensional solutions. They are related to the variations of transverse shear and normal stresses computed at specific points for a simply supported bending problem. Reddy, Cho-Parmerter and (a modified version of) Beakou-Touratier theories have been retained for comparisons. Extended versions of these theories, able to manage the normal stretching, are also considered. All these theories can be emulated by the kinematic field of the present model thanks to the adaptation of the five warping functions. Results of all these theories are confronted and compared to analytical solutions, for the bending of simply supported plates. Various plates are considered, ...
Drainage Basins used for Development of the Watershed Regressions for Pesticides (WARP) Model, 2012
U.S. Geological Survey, Department of the Interior — This data set contains 204 drainage basin boundaries for U.S. Geological Survey (USGS) stream sites analyzed in the Watershed Regressions for Pesticides (WARP)...
Stone, Wesley W.; Gilliom, Robert J.
2009-01-01
Regression models for predicting atrazine concentrations in streams were updated by incorporating refined annual atrazine-use estimates and by adding an explanatory variable representing annual precipitation characteristics. The updated Watershed Regressions for Pesticides (WARP) models enable improved predictions of specific pesticide-concentration statistics for unmonitored streams. for unmonitored streams. Separate WARP regression models were derived for selected percentiles (5th, 10th, 15th, 25th, 50th, 75th, 85th, 90th and 95th), annual mean, annual maximum, and annual maximum moving-average (21-, 60-, and 90-day durations) concentration statistics. Development of the regression models involved the same model-development data, model-validation data, and regression methods as those used in the original development of WARP. The original WARP models were based on atrazine-use estimates from either 1992 or 1997. This update of the WARP models incorporates annual atrazine-use estimates. In addition, annual precipitation data were evaluated as potential explanatory variables. as potential explanatory variables. The updated WARP models include the same five explanatory variables and transformations that were used in the original WARP models, including the new annual atrazine-use data. The models also include a sixth explanatory variable, total precipitation during May and June of the year of sampling. The updated WARP models account for as much as 82 percent of the variability in the concentration statistics among the 112 sites used for model development, whereas previous WARP models accounted for no more than 77 percent. Concentration statistics predicted by the 95th percentile, annual mean, annual maximum and annual maximum moving-average concentration models were within a factor of 10 of the observed concentration statistics for most of the model development and validation sites. Overall, performance of the models for the development and validation sites supports
Improvement of uneven warp tension distribution using a sectional warp beam device%使用分段经轴改善经纱张力不匀
Institute of Scientific and Technical Information of China (English)
F. Neumann; A. Hehl; T. Harbers; T. Gries; 陈杰（译）; 李毓陵（译）
2012-01-01
织物宽度方向的经纱张力不匀将会造成织造困难并导致织物质量下降。目前，纱线长度补偿使经纱张力均匀化从技术上讲是不可能实现的。德国亚琛工业大学纺织技术研究所（ITA），正在对一个有望减少经纱张力不匀的方式进行可行性和影响的研究。分段经轴系统可用于提高织物质量和制造过程的稳定性，进而提高织造效率，普通经轴被10个很窄的、分别独立控制的分段织轴所取代。%Inhomogeneous warp tension across the fabric width leads to weaving process difficulties and results in poor fabric quality. At present, yarn length compensation and thereby homogenization of warp tension is techni- cally not possible. At Institut far Textiltechnik der RWTH Aachen University (ITA), Aachen/Germany, the feasibility of a promising attempt to reduce warp tension inhomogenity and its effects is being researched. A system of sectional warp beams has been developed to increase fabric quality, process stability and there- by weaving productivity. The common warp beam is replaced by 10 narrow, individually controlled sectional warp beams.
On the Mean Curvature of Semi-Riemannian Graphs in Semi-Riemannian Warped Products
Indian Academy of Sciences (India)
Zonglao Zhang
2012-08-01
We investigate the mean curvature of semi-Riemannian graphs in the semi-Riemannian warped product $M× f\\mathbb{R}_$, where is a semi-Riemannian manifold, $\\mathbb{R}_$ is the real line $\\mathbb{R}$ with metric $ dt^2( =± 1)$, and $f:M→ \\mathbb{R}^+$ is the warping function. We obtain an integral formula for mean curvature and some results dealing with estimates of mean curvature, among these results is a Heinz–Chern type inequality.
Parametric Study on the Influence of Warping Deformation upon Natural Frequencies of Die Springs
Directory of Open Access Journals (Sweden)
Ying Hao
2016-01-01
Full Text Available The free vibrational characteristics of die springs are examined by Riccati transfer matrix method in this study. The warping deformation of spring’s cross section, as a new design factor, is incorporated into the differential equation of motion. Numerical simulations show that the warping deformation is a significant role of the behavior of natural frequencies of die springs and should be considered carefully. Approximately 40% of the errors may occur if warping is neglected. The change laws of warping effect with the parameter variations of springs are also explored, including the height-to-width ratio of the cross section, the cylinder diameter, the helix pitch angle, and the number of coils. The warping effect exhibits the most remarkable changes with the variation in the height-to-width ratio of the cross section. However, this effect is not fairly sensitive to the changes in other parameters, and it is particularly significant when the cross section is relatively narrow regardless of the changes in other parameters. This study evidently answers the key scientific question: “under what working condition should the warping effect be considered or ignored?” The analysis results can be used to guide spring designers in engineering.
Overcoming the Educational Time Warp: Anticipating a Different Future
Directory of Open Access Journals (Sweden)
Garry Jacobs
2015-10-01
Full Text Available Education abridges the time required for individual and social progress by preserving and propagating the essence of human experience. It delivers to youth the accumulated knowledge of countless past generations in an organized and abridged form, so that future generations can start off with all the capacities acquired by their predecessors. However, today education confronts a serious dilemma. We are living in an educational time warp. There is a growing gap between contemporary human experience and what is taught in our educational system and that gap is widening rapidly with each passing year. Today humanity confronts challenges of unprecedented scope, magnitude and intensity. The incremental development of educational content and pedagogy in recent decades has not kept with the ever-accelerating pace of technological and social evolution. Education is also subject to a generational time warp resulting from the fact that many of today’s teachers were educated decades ago during very different times and based on different values and perspectives. The challenge of preparing youth for the future is exasperated by the fact that the future for which we are educating youth does not yet exist and to a large extent is unknown or unknowable. The resulting gap between the content of education and societal needs inhibits our capacity to anticipate and effectively respond to social problems. All these factors argue for a major reorientation of educational content and pedagogy from transmission of acquired knowledge based on past experience to development of the knowledge, skills and capacities of personality needed in a future we cannot clearly envision. We may not be able to anticipate the precise nature of the future, but we can provide an education based on the understanding that it will be very different from the present. In terms of content, the emphasis needs to shift from facts regarding the actual state of affairs in the past, present and
Stark, Christopher C.; Schneider, Glenn; Weinberger, Alycia J.; Debes, John H.; Grady, Carol A.; Jang-Condell, Hannah; Kuchner, Marc J.
2014-01-01
New multi-roll coronagraphic images of the HD181327 debris disk obtained using the Space Telescope Imaging Spectrograph on board the Hubble Space Telescope reveal the debris ring in its entirety at high signal-to-noise ratio and unprecedented spatial resolution. We present and apply a new multi-roll image processing routine to identify and further remove quasi-static point-spread function-subtraction residuals and quantify systematic uncertainties. We also use a new iterative image deprojection technique to constrain the true disk geometry and aggressively remove any surface brightness asymmetries that can be explained without invoking dust density enhancements/ deficits. The measured empirical scattering phase function for the disk is more forward scattering than previously thought and is not well-fit by a Henyey-Greenstein function. The empirical scattering phase function varies with stellocentric distance, consistent with the expected radiation pressured-induced size segregation exterior to the belt. Within the belt, the empirical scattering phase function contradicts unperturbed debris ring models, suggesting the presence of an unseen planet. The radial profile of the flux density is degenerate with a radially varying scattering phase function; therefore estimates of the ring's true width and edge slope may be highly uncertain.We detect large scale asymmetries in the disk, consistent with either the recent catastrophic disruption of a body with mass greater than 1% the mass of Pluto, or disk warping due to strong interactions with the interstellar medium.
Starch Modifications to Improve the Paste Stabilities Both in Phase and Viscosity for Warp Sizing
Institute of Scientific and Technical Information of China (English)
ZHU Zhi-feng; YU Jie; YU Cui-yun
2005-01-01
An attempt has been made to improve the paste stabilities both in viscosity of a hot starch paste and in phase of a starch-polyvinyl alcohol blend paste for warp sizing. The phase stability was evaluated in terms of the initial demixing time, and the volume percentage of polyvinyl alcohol separated. It was found that starch cross-linking is harmful to the phase stability of a starch-polyvinyl alcohol blend paste no matter what a type of polyvinyl alcohol is used,although the cross-linking is an effective technique for stabilizing the viscosity of a hot starch paste. The separation rate and extent all increase with the increase in the cross-linking degree of starch. However, this defect can be eliminated through introducing quaternary ammonium groups into crosslinked starch molecules. Evident effect can be achieved when the degree of substitution is as less as0.021. Generally, increase in the DS reduces the separation rate and extent, and thereby raising the phase stability.Moreover, the effects of both starch content and PVA type on the separation are also considered. Cationization after starch cross-linking shows improved stabilities both in viscosity and phase.
Confronting diphoton resonance with cascade decays in warped gravity
Dillon, Barry M; Lee, Hyun Min; Park, Myeonghun
2016-01-01
We consider a Kaluza-Klein (KK) graviton interpretation of the diphoton excesses observed recently at the LHC. The radion, the modulus of extra dimension, appears naturally light due to classical scale invariance in this scenario. Thus, due to the presence of a sizable wavefunction overlap in the extra dimension between the KK graviton and the radion, the KK graviton can decay largely into a pair of radions, each of which decays into a pair of collimated photons, the so called photon-jet. We discuss the photon-jet scenario in setups with warped extra dimension that are consistent with current limits from direct searches and electroweak precision data. One scenario is with suppressed couplings of the KK graviton to the Higgs and fermions, and another scenario is a holographic composite Higgs model with large couplings of the KK graviton to Higgs and top quark included. We discuss the bounds on the light radion and the possibility of distinguishing the photon-jet scenario with the angular distributions of photo...
Conserved charges in timelike Warped-AdS$_3$ spaces
Donnay, L; Giribet, G; Goya, A; Lavia, E
2015-01-01
We consider the timelike version of Warped Anti-de Sitter space (WAdS), which corresponds to the three-dimensional section of the G\\"{o}del solution of four-dimensional cosmological Einstein equations. This geometry presents closed timelike curves (CTCs), which are inherited from its four-dimensional embedding. In three dimensions, this type of solutions can be supported without matter provided the graviton acquires mass. Here, among the different ways to consistenly give mass to the graviton in three dimensions, we consider the parity-even model known as New Massive Gravity (NMG). In the bulk of timelike WAdS$_{3}$ space, we introduce defects that, from the three-dimensional point of view, represent spinning massive particle-like objects. For this type of sources, we investigate the definition of quasi-local gravitational energy as seen from infinity, far beyond the region where the CTCs appear. We also consider the covariant formalism applied to NMG to compute the mass and the angular momentum of spinning p...
Dynamics of warped flux compactifications with backreacting anti-branes
Junghans, Daniel
2014-01-01
We revisit the effective low-energy dynamics of the volume modulus in warped flux compactifications with anti-D3-branes in order to analyze the prospects for meta-stable de Sitter vacua and brane inflation along the lines of KKLT/KKLMMT. At the level of the 10d supergravity solution, anti-branes in flux backgrounds with opposite charge are known to source singular terms in the energy densities of the bulk fluxes, which led to a debate on the consistency of such constructions in string theory. A straightforward yet non-trivial check of the singular solution is to verify that its dimensional reduction in the large-volume limit reproduces the 4d low-energy dynamics expected from known results where the anti-branes are treated as a probe. Taking into account the anti-brane backreaction in the effective scalar potential, we find that both the volume scaling and the coefficient of the anti-brane uplift term are in exact agreement with the probe potential if the singular fluxes satisfy a certain near-brane boundary ...
QCD Color Glass Condensate Model in Warped Brane Models
Ziaeepour, H
2004-01-01
Hadron-hadron interaction and Deep Inelastic Scattering (DIS) at very high energies is dominated by events at small-$x_B$ regime. Interesting and complex physical content of this regime is described by a phenomenological model called McLerran-Venugopalan Color Glass Condensate (MVCGC) model. The advantage of this formalism is the existence of a renormalization-type equation which relates directly observable low energy (small-$x_B$) physics to high energy scales where one expects the appearance of phenomena beyond Standard model. After a brief argument about complexity of observations and their interpretation, we extend CGC to warped space-times with brane boundaries and show that in a hadron-hadron collision or DIS all the events - and not just hard processes - have an extended particle distribution in the bulk. In other word, particles living on the visible brane escape to the bulk. For an observer on the brane the phenomenon should appear as time decoherence in the outgoing particles or missing energy, depe...
Axion monodromy inflation with warped KK-modes
Directory of Open Access Journals (Sweden)
Arthur Hebecker
2016-03-01
Full Text Available We present a particularly simple model of axion monodromy inflation: Our axion is the lowest-lying KK-mode of the RR-2-form-potential C2 in the standard Klebanov–Strassler throat. One can think of this inflaton candidate as being defined by the integral of C2 over the S2 cycle of the throat. It obtains an exponentially small mass from the IR-region in which the S2 shrinks to zero size. Crucially, the S2 cycle has to be shared between two throats, such that the second locus where the S2 shrinks is also in a warped region. Well-known problems like the potentially dangerous back-reaction of brane/antibrane pairs and explicit supersymmetry breaking are not present in our scenario. The inflaton back-reaction on the geometry turns out to be controlled by the string coupling gs. We hope that our setting is simple enough for many critical consistency issues of large-field inflation in string theory to be addressed at a quantitative level.
Axion monodromy inflation with warped KK-modes
Energy Technology Data Exchange (ETDEWEB)
Hebecker, Arthur; Moritz, Jakob; Witkowski, Lukas T. [Heidelberg Univ. (Germany). Inst. for Theoretical Physics; Westphal, Alexander [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)
2015-12-15
We present a particularly simple model of axion monodromy inflation: Our axion is the lowest-lying KK-mode of the RR-2-form-potential C{sub 2} in the standard Klebanov-Strassler throat. One can think of this inflaton candidate as being defined by the integral of C{sub 2} over the S{sup 2} cycle of the throat. It obtains an exponentially small mass from the IR-region in which the S{sup 2} shrinks to zero size. Crucially, the S{sup 2} cycle has to be shared between two throats, such that the second locus where the S{sup 2} shrinks is also in a warped region. Well-known problems like the potentially dangerous back-reaction of brane/antibrane pairs and explicit supersymmetry breaking are not present in our scenario. The inflaton back-reaction on the geometry turns out to be controlled by the string coupling g{sub s}. We hope that our setting is simple enough for many critical consistency issues of large-field inflation in string theory to be addressed at a quantitative level.
WOBBLING AND PRECESSING JETS FROM WARPED DISKS IN BINARY SYSTEMS
Energy Technology Data Exchange (ETDEWEB)
Sheikhnezami, Somayeh [School of Astronomy, Institute for Research in Fundamental Sciences (IPM), Tehran (Iran, Islamic Republic of); Fendt, Christian, E-mail: nezami@mpia.de, E-mail: fendt@mpia.de [Max Planck Institute for Astronomy, Heidelberg (Germany)
2015-12-01
We present results of the first ever three-dimensional (3D) magnetohydrodynamic (MHD) simulations of the accretion–ejection structure. We investigate the 3D evolution of jets launched symmetrically from single stars but also jets from warped disks in binary systems. We have applied various model setups and tested them by simulating a stable and bipolar symmetric 3D structure from a single star–disk–jet system. Our reference simulation maintains a good axial symmetry and also a bipolar symmetry for more than 500 rotations of the inner disk, confirming the quality of our model setup. We have then implemented a 3D gravitational potential (Roche potential) due by a companion star and run a variety of simulations with different binary separations and mass ratios. These simulations show typical 3D deviations from axial symmetry, such as jet bending outside the Roche lobe or spiral arms forming in the accretion disk. In order to find indications of precession effects, we have also run an exemplary parameter setup, essentially governed by a small binary separation of only ≃200 inner disk radii. This simulation shows a strong indication that we observe the onset of a jet precession caused by the wobbling of the jet-launching disk. We estimate the opening angle of the precession cone defined by the lateral motion of the jet axis to be about 4° after about 5000 dynamical time steps.
Warps and waves in fully cosmological models of galactic discs
Gómez, Facundo A; Grand, Robert J J; Marinacci, Federico; Springel, Volker; Pakmor, Rüdiger
2016-01-01
Recent studies have revealed an oscillating asymmetry in the vertical structure of the Milky Way's disc. Here we analyze 16 high-resolution, fully cosmological simulations of the evolution of individual Milky Way-sized galaxies, carried out with the MHD code AREPO. At redshift zero, about $70\\%$ of our galactic discs show strong vertical patterns, with amplitudes that can exceed 2 kpc. Half of these are typical `integral sign' warps. The rest are oscillations similar to those observed in the Milky Way. Such structures are thus expected to be common. The associated mean vertical motions can be as large as 30 km/s. Cold disc gas typically follows the vertical patterns seen in the stars. These perturbations have a variety of causes: close encounters with satellites, distant flybys of massive objects, accretion of misaligned cold gas from halo infall or from mergers. Tidally induced vertical patterns can be identified in both young and old stellar populations, whereas those originating from cold gas accretion are...
Weaving and bonding method to prevent warp and fill distortion
Farley, Gary L. (Inventor)
1997-01-01
A method to prevent fiber distortion in textile materials employed in a modified weaving process. In a first embodiment, a tacifier in powder form is applied to the yarn and melted while on the fabric. Cool air is then supplied after the tacifier has melted to expedite the solidification of the tacifier. In a second embodiment, a solution form of a tacifier is used by dissolving the tacifier into a solvent that has a high evaporation rate. The solution is then sprayed onto the fabric or fill yarn as each fill yarn is inserted into a shed of the fabric. A third embodiment applies the tacifier in a liquid form that has not been dissolved in a solvent. That is, the tacifier is melted and is sprayed as a liquid onto the fabric or fill yarn as it is being extracted from a fill yarn spool prior to the fill yarn being inserted into the shed of the fabric. A fourth embodiment employs adhesive yarns contained as an integral part of the warp or fill yarn. Additional tacifier material is not required because a matrix is used as the tacifier. The matrix is then locally melted using heating elements on clamping bars or take-up rollers, is cooled, if necessary, and solidified.
Warped Higgsless Models with IR-Brane Kinetic Terms
Davoudiasl, H; Lillie, Benjamin Huntington; Rizzo, T G
2004-01-01
We examine a warped Higgsless $SU(2)_L\\times SU(2)_R\\times U(1)_{B-L}$ model in 5--$d$ with IR(TeV)--brane kinetic terms. It is shown that adding a brane term for the $U(1)_{B-L}$ gauge field does not affect the scale ($\\sim 2-3$ TeV) where perturbative unitarity in $W_L^+ W_L^- \\to W_L^+ W_L^-$ is violated. This term could, however, enhance the agreement of the model with the precision electroweak data. In contrast, the inclusion of a kinetic term corresponding to the $SU(2)_D$ custodial symmetry of the theory delays the unitarity violation in $W_L^\\pm$ scattering to energy scales of $\\sim 6-7$ TeV for a significant fraction of the parameter space. This is about a factor of 4 improvement compared to the corresponding scale of unitarity violation in the Standard Model without a Higgs. We also show that null searches for extra gauge bosons at the Tevatron and for contact interactions at LEP II place non-trivial bounds on the size of the IR-brane terms.
A Model of Lepton Masses from a Warped Extra Dimension
Csáki, C; Grojean, Christophe; Grossman, Y
2008-01-01
In order to explain the non-hierarchical neutrino mixing angles and the absence of lepton flavor violating processes in the context of warped extra dimensions one needs to introduce bulk flavor symmetries. We present a simple model of lepton masses and mixings in RS models based on the A4 non-abelian discrete symmetry. The virtues of this choice are: (i) the natural appearance of the tri-bimaximal mixing pattern; (ii) the complete absence of tree-level flavor violations in the neutral sector; (iii) the absence of flavor gauge bosons; (iv) the hierarchies in the charged lepton masses are explained via wave-function overlaps. We present the minimal field content and symmetry breaking pattern necessary to obtain a successful model of this type. The bounds from electroweak precision measurements allow the KK mass scale to be as low as 3 TeV. Tree-level lepton flavor violation is absent in this model, while the loop induced mu -> e gamma branching fraction is safely below the experimental bound.
LHC Signals from Cascade Decays of Warped Vector Resonances
Agashe, Kaustubh S.; Du, Peizhi; Hong, Sungwoo; Kim, Doojin; Mishra, Rashmish K.
2017-01-01
Recently (arXiv:1608.00526), a new framework for warped higher-dimensional compactifications with "bulk" standard model (SM) was proposed: in addition to the UV (Planck scale) and IR (a couple of TeV) branes, there is an intermediate brane, taken to be around 10 TeV. The SM matter and Higgs fields propagate from the UV brane down to this intermediate brane only, while gauge and gravity fields propagate in the entire bulk. Such a configuration renders the lightest gauge Kaluza-Klein (KK) states within LHC reach, simultaneously satisfying flavor and CP constraints. In addition, the usual leading decay modes of the lightest KK gauge bosons into top and Higgs bosons are suppressed. This effect permits erstwhile subdominant channels to become significant. These include flavor-universal decays to SM fermions and Higgs bosons, and a novel channel - decay to a radion and a SM gauge boson, followed by radion decay to a pair of SM gauge bosons. In this work, we first delineate the parameter space where the above mentio...
LHC Signals from Cascade Decays of Warped Vector Resonances
Agashe, Kaustubh S.; Du, Peizhi; Hong, Sungwoo; Kim, Doojin; Mishra, Rashmish K.
2016-01-01
Recently (arXiv:1608.00526), a new framework for warped higher-dimensional compactifications with "bulk" standard model (SM) was proposed: in addition to the UV (Planck scale) and IR (a couple of TeV) branes, there is an intermediate brane, taken to be around 10 TeV. The SM matter and Higgs fields propagate from the UV brane down to this intermediate brane only, while gauge and gravity fields propagate in the entire bulk. Such a configuration renders the lightest gauge Kaluza-Klein (KK) states within LHC reach, simultaneously satisfying flavor and CP constraints. In addition, the usual leading decay modes of the lightest KK gauge bosons into top and Higgs bosons are suppressed. This effect permits erstwhile subdominant channels to become significant. These include flavor-universal decays to SM fermions and Higgs bosons, and a novel channel - decay to a radion and a SM gauge boson, followed by radion decay to a pair of SM gauge bosons. In this work, we first delineate the parameter space where the above mentio...
Moduli instability in warped compactification - 4D effective theory approach
Arroja, F; Arroja, Frederico; Koyama, Kazuya
2006-01-01
We consider a 5D BPS dilatonic two brane model which reduces to the Randall-Sundrum model or the Horava-Witten theory for a particular choice of parameters. Recently new dynamical solutions were found by Chen et al., which describe a moduli instability of the warped geometry. Using a 4D effective theory derived by solving the 5D equations of motion, based on the gradient expansion method, we show that the exact solution of Chen et. al. can be reproduced within the 4D effective theory and we identify the origin of the moduli instability. We revisit the gradient expansion method with a new metric ansatz to clarify why the 4D effective theory solution can be lifted back to an exact 5D solution. Finally we argue against a recent claim that the 4D effective theory allows a much wider class of solutions than the 5D theory and provide a way to lift solutions in the 4D effective theory to 5D solutions perturbatively in terms of small velocities of the branes.
Axion Monodromy Inflation with Warped KK-Modes
Hebecker, Arthur; Westphal, Alexander; Witkowski, Lukas T
2015-01-01
We present a particularly simple model of axion monodromy inflation: Our axion is the lowest-lying KK-mode of the RR-2-form-potential $C_2$ in the standard Klebanov-Strassler throat. One can think of this inflaton candidate as being defined by the integral of $C_2$ over the $S^2$ cycle of the throat. It obtains an exponentially small mass from the IR-region in which the $S^2$ shrinks to zero size. Crucially, the $S^2$ cycle has to be shared between two throats, such that the second locus where the $S^2$ shrinks is also in a warped region. Well-known problems like the potentially dangerous back-reaction of brane/antibrane pairs and explicit supersymmetry breaking are not present in our scenario. The inflaton back-reaction on the geometry turns out to be controlled by the string coupling $g_s$. We hope that our setting is simple enough for many critical consistency issues of large-field inflation in string theory to be addressed at a quantitative level.
On Closed Timelike Curves and Warped Brane World Models
Slagter, Reinoud Jan
2012-01-01
At first glance, it seems possible to construct in general relativity theory causality violating solutions. The most striking one is the Gott spacetime. Two cosmic strings, approaching each other with high velocity, could produce closed timelike curves. It was quickly recognized that this solution violates physical boundary conditions. The effective one particle generator becomes hyperbolic, so the center of mass is tachyonic. On a 5-dimensional warped spacetime, it seems possible to get an elliptic generator, so no obstruction is encountered and the velocity of the center of mass of the effective particle has an overlap with the Gott region. So a CTC could, in principle, be constructed. However, from the effective 4D field equations on the brane, which are influenced by the projection of the bulk Weyl tensor on the brane, it follows that no asymptotic conical space time is found, so no angle deficit as in the 4D counterpart model. This could also explain why we do not observe cosmic strings.
B-factory Signals for a Warped Extra Dimension
Agashe, K; Soni, A; Agashe, Kaustubh; Perez, Gilad; Soni, Amarjit
2004-01-01
We study predictions for B-physics in a class of models, recently introduced, with a non-supersymmetric warped extra dimension. In these models few ($\\sim 3$) TeV Kaluza-Klein masses are consistent with electroweak data due to bulk custodial symmetry. Furthermore, there is an analog of GIM mechanism which is violated by the heavy top quark (just as in SM) leading to striking signals at $B$-factories: (i) New Physics (NP) contributions to $\\Delta F= 2$ transitions are comparable to SM. This implies that, within this NP model, the success of the SM unitarity triangle fit is a ``coincidence''. Thus, clean extractions of unitarity angles via e.g. $B \\to \\pi \\pi,\\rho \\pi, \\rho \\rho, DK$ are likely to be affected, in addition to O(1) deviation from SM prediction in $B_s$ mixing. (ii) O(1) deviation from SM predictions for $B \\to X_s l^+ l^-$ in rate as well as in forward-backward and direct CP asymmetry. (iii) Large mixing-induced CP asymmetry in radiative B decays, wherein the SM unamibgously predicts very small a...
Generalized Gravitational Entropy for Warped Anti-de Sitter Space
Song, Wei; Wen, Qiang; Xu, Jianfei
2016-07-01
For spacetimes that are not asymptotic to anti-de Sitter (non AAdS) space, we adapt the Lewkowycz-Maldacena procedure to find the holographic entanglement entropy. The key observation, which to our knowledge is not very well appreciated, is that asymptotic boundary conditions play an essential role on extending the replica trick to the bulk. For non AAdS, we expect the following three main modifications: (1) the expansion near the special surface has to be compatible with the asymptotic expansion; (2) periodic conditions are imposed to coordinates on the phase space with diagonalized symplectic structure, not to all fields appearing in the action; (3) evaluating the entanglement functional using the boundary term method amounts to evaluating the presymplectic structure at the special surface, where some additional exact form may contribute. An explicit calculation is carried out for three-dimensional warped anti-de Sitter spacetime (WAdS3 ) in a consistent truncation of string theory, the so-called S -dual dipole theory. It turns out that the generalized gravitational entropy in WAdS3 is captured by the least action of a charged particle in WAdS3 space, or equivalently, by the geodesic length in an auxiliary AdS3 . Consequently, the bulk calculation agrees with the CFT results, providing another piece of evidence for the WAdS3/CFT2 correspondence.
Bulk gauge fields in warped space and localized supersymmetry breaking
Energy Technology Data Exchange (ETDEWEB)
Chacko, Z.; Ponton, Eduardo
2003-11-01
We consider five dimensional supersymmetric warped scenarios in which the Standard Model quark and lepton fields are localized on the ultraviolet brane, while the Standard Model gauge fields propagate in the bulk. Supersymmetry is assumed to be broken on the infrared brane. The relative sizes of supersymmetry breaking effects are found to depend on the hierarchy between the infrared scale and the weak scale. If the infrared scale is much larger than the weak scale the leading supersymmetry breaking effect on the visible brane is given by gaugino mediation. The gaugino masses at the weak scale are proportional to the square of the corresponding gauge coupling, while the dominant contribution to the scalar masses arises from logarithmically enhanced radiative effects involving the gaugino mass that are cutoff at the infrared scale. While the LSP is the gravitino, the NLSP which is the stau is stable on collider time scales. If however the infrared scale is close to the weak scale then the effects of hard supersymmetry breaking operators on the scalar masses can become comparable to those from gaugino mediation. These operators alter the relative strengths of the couplings of gauge bosons and gauginos to matter, and give loop contributions to the scalar masses that are also cutoff at the infrared scale. The gaugino masses, while exhibiting a more complicated dependence on the corresponding gauge coupling, remain hierarchical and become proportional to the corresponding gauge coupling in the limit of strong supersymmetry breaking. The scalar masses are finite and a loop factor smaller than the gaugino masses. The LSP remains the gravitino.
Warping and tearing of misaligned circumbinary disks around eccentric SMBH binaries
Hayasaki, Kimitake; Okazaki, Atsuo T; Jung, Taehyun; Zhao, Guangyao; Naito, Tsuguya
2015-01-01
We study the warping and tearing of a geometrically thin, non-self-gravitating disk surrounding binary supermassive black holes on an eccentric orbit. The circumbinary disk is significantly misaligned with the binary orbital plane, and is subject to the time-dependent tidal torques. In principle, such a disk is warped and precesses, and is torn into mutually misaligned rings in the region, where the tidal precession torques are stronger than the local viscous torques. We derive the tidal-warp and tearing radii of the misaligned circumbinary disks around eccentric SMBH binaries. We find that in disks with the viscosity parameter, alpha, larger than a critical value depending on the disk aspect ratio, the disk warping appears outside the tearing radius. This condition is expressed as alpha > sqrt{H/3r} for H/r ~<0.1, where H is the disk scale height. If alpha < sqrt{H/3r}, only the disk tearing occurs because the tidal warp radius is inside the tearing radius, where most of disk material is likely to rapi...
Conformal Array Pattern Synthesis Using a Hybrid WARP/2LB-MOPSO Algorithm
Directory of Open Access Journals (Sweden)
Roghieh Karimzadeh Baee
2012-01-01
Full Text Available This paper addresses conformal array synthesis as a constrained multiobjective optimization problem. Simultaneous reduction of side lobe level (SLL and cross-polarization (XPL level is aimed with a constraint on main beam direction. A hybrid of weighted alternating reverse projection (WARP and two local best multiobjective particle swarm optimization (2LB-MOPSO is proposed to optimize the pattern. First, the WARP method finds a moderate and feasible solution. Second, 2LB-MOPSO begins with an initial population including the solution of WARP and penalty functions for constraint handling. Involving WARP result in the initial population of 2LB-MOPSO leads to higher convergence rate, avoiding local extermum traps and less sensitivity to penalty functions. Compared to WARP method which stagnates rapidly, the proposed hybrid method gives better SLL and XPL after adequate iterations. In addition, as 2LB-MOPSO offers a set of optimum solutions (Pareto front instead of a single solution, this method provides more degrees of freedom in selection of proper practical arrays. Finally, to examine the mutual coupling consideration in array design, the same procedure was applied ignoring the mutual coupling between elements. The results show that the SLL and XPL strongly depend on mutual coupling.
Generation of galactic disc warps due to intergalactic accretion flows onto the disc
López-Corredoira, M; Beckman, J E
2002-01-01
A new method is developed to calculate the amplitude of the galactic warps generated by a torque due to external forces. This takes into account that the warp is produced as a reorientation of the different rings which constitute the disc in order to compensate the differential precession generated by the external force, yielding a uniform asymptotic precession for all rings. Application of this method to gravitational tidal forces in the Milky Way due to the Magellanic Clouds leads to a very low amplitude of the warp. If the force were due to an extragalactic magnetic field, its intensity would have to be very high, to generate the observed warps. An alternative hypothesis is explored: the accretion of the intergalactic medium over the disk. A cup-shaped distortion is expected, due to the transmission of the linear momentum; but, this effect is small and the predominant effect turns out to be the transmission of angular momentum, i.e. a torque giving an integral-sign shape warp. The torque produced by a flow...
Experimental Investigation About Stamping Behaviour of 3D Warp Interlock Composite Preforms
Dufour, Clément; Wang, Peng; Boussu, François; Soulat, Damien
2014-10-01
Forming of continuous fibre reinforcements and thermoplastic resin commingled prepregs can be performed at room temperature due to its similar textile structure. The "cool" forming stage is better controlled and more economical. The increase of temperature and the resin consolidation phases after the forming can be carried out under the isothermal condition thanks to a closed system. It can avoid the manufacturing defects easily experienced in the non-isothermal thermoforming, in particular the wrinkling [1]. Glass/Polypropylene commingled yarns have been woven inside different three-dimensional (3D) warp interlock fabrics and then formed using a double-curved shape stamping tool. The present study investigates the in-plane and through-thickness behaviour of the 3D warp interlock fibrous reinforcements during forming with a hemispherical punch. Experimental data allow analysing the forming behaviour in the warp and weft directions and on the influence of warp interlock architectures. The results point out that the layer to layer warp interlock preform has a better stamping behaviour, in particular no forming defects and good homogeneity in thickness.
Theory of Band Warping and its Effects on Thermoelectronic Transport Properties
Mecholsky, Nicholas; Resca, Lorenzo; Pegg, Ian; Fornari, Marco
2015-03-01
Transport properties of materials depend upon features of band structures near extrema in the BZ. Such features are generally described in terms of quadratic expansions and effective masses. Such expansions, however, are permissible only under strict conditions that are sometimes violated by materials. Suggestive terms such as ``band warping'' have been used to refer to such situations and ad hoc methods have been developed to treat them. We develop a generally applicable theory, based on radial expansions, and a corresponding definition of angular effective mass which also accounts for effects of band non-parabolicity and anisotropy. Further, we develop precise procedures to evaluate band warping quantitatively and as an example we analyze the warping features of valence bands in silicon using first-principles calculations and we compare those with semi-empirical models. We use our theory to generalize derivations of transport coefficients for cases of either single or multiple electronic bands, with either quadratically expansible or warped energy surfaces. We introduce the transport-equivalent ellipsoid and illustrate the drastic effects that band warping can induce on thermoelectric properties using multi-band models. Vitreous State Laboratory and Samsung's GRO program.
More, Anupreeta; Verma, Aprajita; Marshall, Philip J.; More, Surhud; Baeten, Elisabeth; Wilcox, Julianne; Macmillan, Christine; Cornen, Claude; Kapadia, Amit; Parrish, Michael; Snyder, Chris; Davis, Christopher P.; Gavazzi, Raphael; Lintott, Chris J.; Simpson, Robert; Miller, David; Smith, Arfon M.; Paget, Edward; Saha, Prasenjit; Küng, Rafael; Collett, Thomas E.
2016-01-01
We report the discovery of 29 promising (and 59 total) new lens candidates from the Canada-France-Hawaii Telescope Legacy Survey (CFHTLS) based on about 11 million classifications performed by citizen scientists as part of the first SPACE WARPS lens search. The goal of the blind lens search was to identify lens candidates missed by robots (the RINGFINDER on galaxy scales and ARCFINDER on group/cluster scales) which had been previously used to mine the CFHTLS for lenses. We compare some properties of the samples detected by these algorithms to the SPACE WARPS sample and find them to be broadly similar. The image separation distribution calculated from the SPACE WARPS sample shows that previous constraints on the average density profile of lens galaxies are robust. SPACE WARPS recovers about 65 per cent of known lenses, while the new candidates show a richer variety compared to those found by the two robots. This detection rate could be increased to 80 per cent by only using classifications performed by expert volunteers (albeit at the cost of a lower purity), indicating that the training and performance calibration of the citizen scientists is very important for the success of SPACE WARPS. In this work we present the SIMCT pipeline, used for generating in situ a sample of realistic simulated lensed images. This training sample, along with the false positives identified during the search, has a legacy value for testing future lens-finding algorithms. We make the pipeline and the training set publicly available.
The Central Charge of the Warped AdS^3 Black Hole
Gupta, Kumar S; Sen, Siddhartha; Sivakumar, M
2010-01-01
The AdS/CFT conjecture offers the possibility of a quantum description for a black hole in terms of a CFT. This has ledto the study of general AdS^3 type black holes with a view to constructing an explicit toy quantum black hole model. Such a CFT description would be characterized by its central charge and the dimensions of its primary fields. Recently the expression for the central charges (C_L, C_R) of the CFT dual to the warped AdS^3 have been determined using asymptotic symmetry arguments. The central charges depend, as expected, on the warping factor. We show that topological arguments, used by Witten to constrain central charges for the BTZ black hole, can be generalized to deal with the warped AdS^3 case. Topology constrains the warped factor to be rational numbers while quasinormal modes are conjectured to give the dimensions of primary fields. We find that in the limit when warping is large or when it takes special rational values the system tends to Witten's conjectured unique CFT's with central cha...
Detailed study of null and time-like geodesics in the Alcubierre Warp spacetime
Müller, Thomas
2011-01-01
The Alcubierre warp spacetime yields a fascinating chance for comfortable interstellar travel between arbitrary distant places without the time dilation effect as in special relativistic flights. Even though the warp spacetime needs exotic matter for its construction and is thus far from being physically feasible, it offers a rich playground for studying geodesics in the general theory of relativity. This paper is addressed to graduate students who have finished a first course in general relativity to give them a deeper inside in the calculation of non-affinely parametrized null and time-like geodesics and a straightforward approach to determine the gravitational lensing effect due to curved spacetime by means of the Jacobi equation. Both topics are necessary for a thorough discussion of the visual effects as observed by a traveller inside the warp bubble or a person looking from outside. The visual effects of the traveller can be reproduced with an interactive Java application.
The Origin of Warped, Precessing Accretion Disks in X-ray Binaries
Maloney, Philip R.; Begelman, Mitchell C.
1997-01-01
The radiation-driven warping instability discovered by Pringle holds considerable promise as the mechanism responsible for producing warped, precessing accretion disks in X-ray binaries. This instability is an inherently global mode of the disk, thereby avoiding the difficulties with earlier models for the precession. Here we follow up on earlier work to study the linear behavior of the instability in the specific context of a binary system. We treat the influence of the companion as an orbit-averaged quadrupole torque on the disk. The presence of this external torque allows the existence of solutions in which the direction of precession of the warp is retrograde with respect to disk rotation, in addition to the prograde solutions that exist in the absence of external torques.
Warped Discrete Cosine Transform-Based Low Bit-Rate Block Coding Using Image Downsampling
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Ertürk Sarp
2007-01-01
Full Text Available This paper presents warped discrete cosine transform (WDCT-based low bit-rate block coding using image downsampling. While WDCT aims to improve the performance of conventional DCT by frequency warping, the WDCT has only been applicable to high bit-rate coding applications because of the overhead required to define the parameters of the warping filter. Recently, low bit-rate block coding based on image downsampling prior to block coding followed by upsampling after the decoding process is proposed to improve the compression performance for low bit-rate block coders. This paper demonstrates that a superior performance can be achieved if WDCT is used in conjunction with image downsampling-based block coding for low bit-rate applications.
The warped galaxy MKN 306 in the interacting system MKN 305/306
Kollatschny, W.; Dietrich, M.
1990-07-01
Optical images and spectra of the interacting galaxy system Mkn 305/306 are presented. Both galaxies have a disturbed morphology, and they show spectra with starburst or poststarburst characteristics as a result of mutual tidal interaction. Mkn 306 is shaped like an integral sign with two strong symmetrical central emission regions. The morphology, the velocity structure, and the optical spectra demonstrate that the galaxy Mkn 306 is seen nearly edge-on with a very strong warp of the stellar disk. The extreme degree of this optical distortion is comparable only with the strongest radio warps so far known; but these radio warps show only the H I gas distribution in the outer galactic regions and not the stellar distribution.
Extension of the non-uniform warping theory to an orthotropic composite beam
Ghazouani, Nejib; El Fatmi, Rached
2010-12-01
This Note proposes an extension to composite section of the non-uniform (out-of-plane) warping beam theory recently established for homogeneous and isotropic beam by R. El Fatmi (C. R. Mecanique 335 (2007) 467-474). For the present work, which constitutes a first step of this extension, the cross-section is assumed to be symmetric and made by orthotropic materials; however, Poisson's effects (called here in-plane warping) are also taken into account. Closed form results are given for the structural behavior of the composite beam and for the expressions of the 3D stresses; these ones, easy to compare with 3D Saint Venant stresses, make clear the additional contribution of the new internal forces induced by the non-uniformity of the (in and out) warpings. As first numerical applications, results on torsion and shear-bending of a cantilever sandwich beam are presented.
Canonical structure of BHT massive gravity in warped AdS3 sector
Yekta, Davood Mahdavian
2016-01-01
We investigate the asymptotic structure of the three dimensional warped anti de sitter black holes in the Bergshoeff, Hohm and Townsend massive gravity using the canonical Hamiltonian formalism. We define the canonical asymptotic guage generators, which produce the conserved charges and the asymptotic symmetry group for the warped anti de sitter black holes. The attained symmetry group is described by a semi direct sum of a Virasoro and a KacMoody algebra. Using the Sugawara construction, we obtain a direct sum of two Virasoro algebras. We show that not only the asymptotic conserved charges satisfy the first law of black hole thermodynamics, but also they lead to the expected Smarr formula for the warped anti de sitter black holes. We also show that the black hole entropy obeys the Cardy formula of the dual conformal field theory .
Computer-Aided Design Method of Warp-Knitted Jacquard Spacer Fabrics
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Li Xinxin
2016-06-01
Full Text Available Based on a further study on knitting and jacquard principles, this paper presents a mathematical design model to make computer-aided design of warp-knitted jacquard spacer fabrics more efficient. The mathematical model with matrix method employs three essential elements of chain notation, threading and Jacquard designing. With this model, the processing to design warp-knitted jacquard spacer fabrics with CAD software is also introduced. In this study, the sports shoes which have separated functional areas according to the feet structure and characteristics of movement are analysed. The results show the different patterns on Jacquard spacer fabrics that are seamlessly stitched with jacquard technics. The computer-aided design method of warp-knitted jacquard spacer fabrics is efficient and simple.
Diphoton excess via Chern-Simons interaction in a warped geometry scenario
Chakrabarty, Nabarun; SenGupta, Soumitra
2016-01-01
We offer an explanation of the recently observed 750 GeV diphoton peak at the Large Hadron Collider (LHC) in terms of an axion related to the 5-dimensional Kalb-Ramond (KR) field in a Randall-Sundrum warped geometry scenario. The KR field, identifiable with bulk torsion, has Chern-Simons interactions with gauge boson pairs. These in turn yield unsuppressed coupling of the torsion to gluon as well as photon pairs in (3+1) dimensions, while the warped geometry enforces ultra-suppressed interaction with fermion pairs . We show that the observed results can be numerically justified when the warp factor is precisely in the range required for stabilisation of the electroweak scale.
Influence of Warp Yarn Tension on Cotton Greige and Dyed Woven Fabric Prosperities
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Uzma Syed
2013-01-01
Full Text Available Fabric properties such as pilling and abrasion resistance and tensile strength vary when greige fabric is processed further. The quality of dyed fabric depends on the quality of greige fabric. Cotton Plain and Twill weave fabrics were woven at three different warp yarn tension and then dyed using monochlorotriazine, Drimerene Red Cl-5B dye gives difference in fabric properties. The ASTM, American International Standards were used to determine the greige and dyed fabric properties. It has been observed fabric woven at proper loom setting or warp yarn tension have high strength, less pilling and abrasion tendency as compared to fabric woven at variant warp yarn tension. Moreover, fabric tenacity is decreased after dyeing whereas, slight difference in pilling and abrasion values is observed after dyeing than that of greige fabric.
WARP model pesticide predictions for EPA reach file 1 segments: 1992-2012
Stone, Wesley W.
2017-01-01
The Watershed Regressions for Pesticides (WARP) models were developed using linear regression methods to establish quantitative linkages between pesticide concentrations measured at U.S. Geological Survey sampling sites and a variety of human-related and natural factors that affect pesticide concentrations in streams. Such factors include pesticide use, soil characteristics, hydrology, and climate - collectively referred to as explanatory variables. Model predictions for multiple pesticides for Environmental Protection Agency River Reach 1 segments are provided in tabular format for the years 1992, 1997, 2002, 2007, and 2012. The WARP models were published in Stone, W.W., Crawford, C.G., and Gilliom, R.J., 2013, Watershed Regressions for Pesticides (WARP) models for predicting stream concentrations of multiple pesticides. Journal of Environmental Quality, 42:1838-1851. http://dx.doi.org/10.2134/jeq2013.05.0179 .
Warped Discs of External Galaxies and their Statistical Studies%星系翘曲盘及其统计研究
Institute of Scientific and Technical Information of China (English)
赵君亮
2012-01-01
河外旋涡星系外区普遍存在翘曲结构,其特征可用若干翘曲参数来描述,包括翘曲角、翘曲半径、不对称度等.一些翘曲星系表已相继发表,并用于相关的统计分析.关于翘曲盘的形成已提出多种理论机制,如星系间的潮汐相互作用、星系际介质的吸积、盘与暗晕的角动量错向以及星系际磁场的作用等.%It has been known from both radio and optical measurements that the disk warps in the outer regions of spiral galaxies are a very common phenomenon, the feature of which can be described by some parameters, such as warp radius, warp angle, warp amplitude, warp asymmetry etc. During the past two decades, various shapes of warped disks have been found, including S-shaped (or integral sign shaped) , U-shaped and L-shaped warps, among which U means that the two warps are not asymmetric with respect to the galactic center, and L means that only one of the two sides of the galaxy is warped.Since the end of the 20 century, catalogues of warps in spirals identified from edge-on galaxies have been published, some of which provide a lot of information on structureparameters of warped disks of more than 500 galaxies. On the basis of these data many statistical analysis and discussions on warped disks have been made in order to investigate the observational frequencies of warps with different types and different environment, and to find possible intrinsic relationships among the warp parameters, which could provide some useful diagnostic indicators of the origin of warps.Generally speaking, observational frequencies of warped galaxies found from both radio and optical measurements are up to 60%-70% or even higher for all the warp samples presently available. This observational fact shows that the warped disk is a permanentstructure, or a transient phenomenon but excited frequently. In a statistical study it was found that the relative fraction of warps among galaxies without nearby companions is
The origin of the warped heliospheric current sheet. Scientific technical report
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Wilcox, J.M.; Scherrer, P.H.; Hoeksema, J.T.
1980-03-01
The warped heliospheric current sheet in early 1976 is calculated from the observed photospheric magnetic field using a potential field method. Comparisons with measurements of the interplanetary magnetic field polarity in early 1976 obtained at several locations in the heliosphere at Helios I, Helios II, Pioneer XI and Earth show a rather detailed agreement between the computed current sheet and the observations. It appears that the large-scale structure of the warped heliospheric current sheet is determined by the structure of the photospheric magnetic field, and that 'ballerina skirt' effects may add small-scale ripples.
Warping the Kähler potential of F-theory/IIB flux compactifications
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Martucci, Luca [Dipartimento di Fisica ed Astronomia “Galileo Galilei' , Università di Padova,and INFN - Sezione di Padova,Via Marzolo 8, 35131 Padova (Italy)
2015-03-13
We identify the low-energy Kähler potential of warped F-theory/IIB flux compactifications whose light spectrum includes universal, Kähler, axionic and mobile D3-brane moduli. The derivation is based on four-dimensional local superconformal symmetry and holomorphy of brane instanton contributions and it reproduces and generalises previous partial results. We compute the resulting kinetic terms, which show their explicit dependence on the warping. The Kähler potential satisfies the no-scale condition and produces, at leading order in the large volume expansion, a specific correction to the unwarped Kähler potential.
Warped AdS{sub 3} black holes in higher derivative gravity theories
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Detournay, Stéphane [Université Libre de Bruxelles and International Solvay Institutes,Physique Théorique et Mathématique,Campus Plaine C.P. 231, B-1050 Bruxelles (Belgium); Douxchamps, Laure-Anne [Université Libre de Bruxelles and International Solvay Institutes,Physique Théorique et Mathématique,Campus Plaine C.P. 231, B-1050 Bruxelles (Belgium); Department of Physics, McGill University,Montréal, QC H3A 2T8 (Canada); Ng, Gim Seng [Department of Physics, McGill University,Montréal, QC H3A 2T8 (Canada); Zwikel, Céline [Université Libre de Bruxelles and International Solvay Institutes,Physique Théorique et Mathématique,Campus Plaine C.P. 231, B-1050 Bruxelles (Belgium)
2016-06-06
We consider warped AdS{sub 3} black holes in generic higher derivatives gravity theories in 2+1 dimensions. The asymptotic symmetry group of the phase space containing these black holes is the semi-direct product of a centrally extended Virasoro algebra and an affine u(1) Kac-Moody algebra. Previous works have shown that in some specific theories, the entropy of these black holes agrees with a Cardy-like entropy formula derived for warped conformal field theories. In this paper, we show that this entropy matching continues to hold for the most general higher derivative theories of gravity. We also discuss the existence of phase transitions.
On the 4D effective theory in warped compactifications with fluxes and branes
Koyama, K; Koyama, K; Arroja, Frederico; Koyama, Kayoko; Koyama, Kazuya
2006-01-01
We present a systematic way to derive the four-dimensional effective theories for warped compactifications with fluxes and branes in the ten-dimensional type IIB supergravity. The ten-dimensional equations of motion are solved using the gradient expansion method and the effective four-dimensional equations of motions are derived by imposing the consistency condition that the total derivative terms with respect to the six-dimensional internal coordinates vanish when integrated over the internal manifold. By solving the effective four-dimensional equations, we can find the gravitational backreaction to the warped geometry due to the dynamics of moduli fields, branes and fluxes.
Jiang, Jin-Wu
2016-06-01
We investigate the strain engineering and the edge effect for mechanical properties in graphene nanoribbons. The free edges of the graphene nanoribbons are warped due to compressive edge stresses. There is a structural transformation for the free edges from the three-dimensional warping configuration to the two-dimensional planar structure at the critical strain ɛc = 0.7%, at which the applied mechanical stress is equal to the intrinsic compressive edge stress. This structural transformation leads to step-like changes in several mechanical properties studied in the present work, including the Young's modulus, the Poisson's ratio, the quality factor of nanomechanical resonators, and the phonon edge mode.
Killing-Yano forms and Killing tensors on a warped space
Krtous, Pavel; Kolar, Ivan
2015-01-01
We formulate several criteria under which the symmetries associated with the Killing and Killing-Yano tensors on the base space can be lifted to the symmetries of the full warped geometry. The procedure is explicitly illustrated on several examples, providing new prototypes of spacetimes admitting such tensors. In particular, we study a warped product of two Kerr-NUT-(A)dS spacetimes and show that it gives rise to a new class of highly symmetric vacuum (with cosmological constant) black hole solutions that inherit many of the properties of the Kerr-NUT-(A)dS geometry.
Energy Technology Data Exchange (ETDEWEB)
Moens, Vince [Ecole Polytechnique Federale de Lausanne (EPFL) (Switzerland)
2014-06-08
The purpose of this guide is to help successive students handle WARP. It outlines the installation of WARP on personal computers as well as super-computers and clusters. It furthermore teaches the reader how to handle the WARP environment and run basic scripts. Lastly it outlines how to execute the current Hollow Electron Beam Lens scripts.
Lee, Jeff
2014-01-01
This paper contends that the spacetime distortions resulting from the experimentally obtainable electric field of a parallel plate capacitor configuration cannot be detected by the White-Juday Warp Field Interferometer [1]. Any post-processing results indicating a vanishing, non-zero difference between the charged and uncharged states of the capacitor are due to local effects rather than spacetime perturbations.
The Stars and Gas in Outer Parts of Galaxy Disks : Extended or Truncated, Flat or Warped?
van der Kruit, P. C.; Funes, JG; Corsini, EM
2008-01-01
I review observations of truncations of stellar disks and models for their origin, compare observations of truncations in moderately inclined galaxies to those in edge-on systems and discuss the relation between truncations and H I-warps and their systematics and origin. Truncations are a common fea
HI study of the warped spiral galaxy NGC5055 : a disk/dark matter halo offset?
Battaglia, G; Fraternali, F; Oosterloo, T; Sancisi, R
2006-01-01
We present a study of the Hi distribution and dynamics of the nearby spiral galaxy NGC 5055 based on observations with the Westerbork Synthesis Radio Telescope. The gaseous disk of NGC5055 extends out to about 40 kpc, equal to 3.5 R-25, and shows a pronounced warp that starts at the end of the brigh
HI study of the warped spiral galaxy NGC5055 : a disk/dark matter halo offset?
Battaglia, G.; Fraternali, F.; Oosterloo, T.; Sancisi, R.
2005-01-01
Abstract: We present a study of the HI distribution and the dynamics of the nearby spiral galaxy NGC5055 based on observations with the Westerbork Synthesis Radio Telescope. The gaseous disk of NGC5055 extends out to about 40 kpc, equal to 3.5 R_25 and shows a pronounced warp, starting at the end of
The WARPS Survey. VIII. Evolution of the Galaxy Cluster X-ray Luminosity Function
Koens, L A; Jones, L R; Ebeling, H; Horner, D J; Perlman, E S; Phillipps, S; Scharf, C A
2012-01-01
We present measurements of the galaxy cluster X-ray Luminosity Function (XLF) from the Wide Angle ROSAT Pointed Survey (WARPS) and quantify its evolution. WARPS is a serendipitous survey of the central region of ROSAT pointed observations and was carried out in two phases (WARPS-I and WARPS-II). The results here are based on a final sample of 124 clusters, complete above a flux limit of 6.5 10E-15 erg/s/cm2, with members out to redshift z ~ 1.05, and a sky coverage of 70.9 deg2. We find significant evidence for negative evolution of the XLF, which complements the majority of X-ray cluster surveys. To quantify the suggested evolution, we perform a maximum likelihood analysis and conclude that the evolution is driven by a decreasing number density of high luminosity clusters with redshift, while the bulk of the cluster population remains nearly unchanged out to redshift z ~ 1.1, as expected in a low density Universe. The results are found to be insensitive to a variety of sources of systematic uncertainty that ...
Alignment of Quasar Polarizations on Large Scales Explained by Warped Cosmic Strings
Slagter, Reinoud Jan
2016-01-01
The recently discovered alignment of quasar polarizations on very large scales could possibly explained by considering cosmic strings on a warped five dimensional spacetime. Compact objects, such as cosmic strings, could have tremendous mass in the bulk, while their warped manifestations in the brane can be consistent with general relativity in 4D. The self-gravitating cosmic string induces gravitational wavelike disturbances which could have effects felt on the brane, i.e., the massive effective 4D modes (Kaluza-Klein modes) of the perturbative 5D graviton. This effect is amplified by the time dependent part of the warp factor. Due to this warp factor, disturbances don't fade away during the expansion of the universe. From a non-linear perturbation analysis it is found that the effective Einstein 4D equations on an axially symmetric spacetime, contain a "back-reaction" term on the righthand side caused by the projected 5D Weyl tensor and can act as a dark energy term. The propagation equations to first order...
Space Warps II. New Gravitational Lens Candidates from the CFHTLS Discovered through Citizen Science
More, Anupreeta; Marshall, Phil; More, Surhud; Baeten, Elisabeth; Wilcox, Julianne; Macmillan, Christine; Cornen, Claude; Kapadia, Amit; Parrish, Michael; Snyder, Chris; Davis, Chris; Gavazzi, Raphael; Lintott, Chris; Simpson, Robert; Miller, David; Smith, Arfon M; Paget, Edward; Saha, Prasenjit; Kueng, Rafael; Collett, Tom; Tecza, Matthias; Baumer, Michael
2015-01-01
We report the discovery of 28 promising and a total of 58 new lens candidates from the CFHT Legacy Survey (CFHTLS) based on about 11 million classifications performed by citizen scientists as part of the first Space Warps lens search. The goal of the blind lens search was to identify lenses missed by lens finding robots (the RingFinder on galaxy scales and ArcFinder on group/cluster scales), which have been previously used to mine the CFHTLS for lenses. We compare some properties of lens samples detected by these algorithms to the SpaceWarps sample and found that they are broadly similar. The image separation distribution calculated from the SpaceWarps discovered sample shows that our previous constraints on the average density profile of the lens population are robust. Space Warps recovers about 60% of the known sample and the new candidates show a richer variety compared to the lenses found by the two robots. We find that analyzing only those classifications which are performed by the high power volunteers,...
Evolution of linear warps in accretion discs and applications to protoplanetary discs in binaries
Foucart, Francois
2014-01-01
The existence of warped accretion discs is expected in a wide variety of astrophysical systems, including circumstellar discs in binaries and discs around binary protostars. A common feature of these discs is that they are perturbed by a misaligned external potential. In this paper, we study the long-term evolution of the disc warp and precession in the case of thick discs (with the dimensionless thickness $H/r$ larger than the viscosity parameter $\\alpha$) in which bending waves can propagate. For small warps, such discs undergo approximately rigid-body precession with a coherent global frequency. We derive the analytical expressions for the warp/twist profiles of the disc and the alignment timescale for a variety of disc models/parameters. Applying our results to circumbinary discs, we find that these discs align with the orbital plane of the binary on a timescale comparable to the global precession time of the disc, and typically much smaller than its viscous timescale. The development of parametric instab...
Springer, P.
1993-01-01
This paper discusses the method in which the Cascade-Correlation algorithm was parallelized in such a way that it could be run using the Time Warp Operating System (TWOS). TWOS is a special purpose operating system designed to run parellel discrete event simulations with maximum efficiency on parallel or distributed computers.
Resistance of i-beams in warping torsion with account for the development of plasticdeformations
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Tusnin Aleksandr Romanovich
2014-01-01
Full Text Available Torsion of thin-walled open-section beams due to restrained warping displacements of cross-section is causing additional stresses, which make a significant contribution to the total stress. Due to plastic deformation there are certain reserves of bearing capacity, identification of which is of significant practical interest. The existing normative documents for the design of steel structures in Russia do not include design factor taking into account the development of plastic deformation during warping torsion. The analysis of thin-walled open-section members with plastic deformation will more accurately determine their load-bearing capacity and requires further research. Reserves of the beams bearing capacity due to the development of plastic deformations are revealed when beams are influenced by bending, as well as tension and compression. The existing methodology of determining these reserves and the plastic shape factor in bending was reviewed. This has allowed understanding how it was possible to solve this problem for warping torsion members and outline possible ways of theoretical studies of the bearing capacity in warping torsion. The authors used theoretical approach in determining this factor for the symmetric I-section beam under the action of bimoment and gave recommendations for the design of torsion members including improved value of plastic shape factor.
CP violation and FCNC in a warped A(4) flavor model
Kadosh, Avihay; Pallante, Elisabetta
2011-01-01
We recently proposed a spontaneous A(4) flavor symmetry breaking scheme implemented in a warped extra dimensional setup to explain the observed pattern of quark and lepton masses and mixings. The quark mixing is absent at leading order in the VEV expansion and it is induced at next-to-leading order
theta(13) and charged lepton flavor violation in "warped" A(4) models
Kadosh, Avihay
2013-01-01
We recently proposed a spontaneous A(4) flavor symmetry breaking scheme implemented in a warped extra dimensional setup to explain the observed pattern of quark and lepton masses and mixings. The main features of this choice are the explanation of fermion mass hierarchies by wave function overlaps,
Characterizing the Galactic warp with Gaia: I. The tilted ring model with a twist
Abedi, H; Aguilar, L A; Figueras, F; Romero-Gomez, M
2015-01-01
We explore the possibility of detecting and characterizing the warp of the stellar disc of our Galaxy using synthetic Gaia data. The availability of proper motions and, for the brightest stars radial velocities, adds a new dimension to this study. A family of Great Circle Cell Counts (GC3) methods is used. They are ideally suited to find the tilt and twist of a collection of rings, which allow us to detect and measure the warp parameters. To test them, we use random realizations of test particles which evolve in a realistic Galactic potential warped adiabatically to various final configurations. In some cases a twist is introduced additionally. The Gaia selection function, its errors model and a realistic 3D extinction map are applied to mimic three tracer populations: OB, A and Red Clump stars. We show how the use of kinematics improves the accuracy in the recovery of the warp parameters. The OB stars are demonstrated to be the best tracers determining the tilt angle with accuracy better than $\\sim0.5$ up to...
Submanifolds in space-time with unphysical extra dimensions, cosmology and warped brane world models
Smolyakov, Mikhail N
2008-01-01
The explicit coordinate transformations which show the equivalence between a four-dimensional spatially flat cosmology and an appropriate submanifold in the flat five-dimensional Minkowski space-time are presented. Analogous procedure is made for the case of five-dimensional warped brane world models. Several examples are presented.
Springer, P.
1993-01-01
This paper discusses the method in which the Cascade-Correlation algorithm was parallelized in such a way that it could be run using the Time Warp Operating System (TWOS). TWOS is a special purpose operating system designed to run parellel discrete event simulations with maximum efficiency on parallel or distributed computers.
Band warping, band non-parabolicity, and Dirac points in electronic and lattice structures
Resca, Lorenzo; Mecholsky, Nicholas A.; Pegg, Ian L.
2017-10-01
We illustrate at a fundamental level the physical and mathematical origins of band warping and band non-parabolicity in electronic and vibrational structures. We point out a robust presence of pairs of topologically induced Dirac points in a primitive-rectangular lattice using a p-type tight-binding approximation. We analyze two-dimensional primitive-rectangular and square Bravais lattices with implications that are expected to generalize to more complex structures. Band warping is shown to arise at the onset of a singular transition to a crystal lattice with a larger symmetry group, which allows the possibility of irreducible representations of higher dimensions, hence band degeneracy, at special symmetry points in reciprocal space. Band warping is incompatible with a multi-dimensional Taylor series expansion, whereas band non-parabolicities are associated with multi-dimensional Taylor series expansions to all orders. Still band non-parabolicities may merge into band warping at the onset of a larger symmetry group. Remarkably, while still maintaining a clear connection with that merging, band non-parabolicities may produce pairs of conical intersections at relatively low-symmetry points. Apparently, such conical intersections are robustly maintained by global topology requirements, rather than any local symmetry protection. For two p-type tight-binding bands, we find such pairs of conical intersections drifting along the edges of restricted Brillouin zones of primitive-rectangular Bravais lattices as lattice constants vary relatively to each other, until these conical intersections merge into degenerate warped bands at high-symmetry points at the onset of a square lattice. The conical intersections that we found appear to have similar topological characteristics as Dirac points extensively studied in graphene and other topological insulators, even though our conical intersections have none of the symmetry complexity and protection afforded by the latter more
Directory of Open Access Journals (Sweden)
Ting-Ting Li
2016-02-01
Full Text Available Elastic warp-knitted composite fabrics with far-infrared emissivity and an anion-releasing property were prepared using bamboo charcoal (BC, copper (Cu, and phase-change material (PCM. The functional composite fabric, which was composed of self-made complex yarns with various twisting degrees and material composition, were created using a rotor twister and ring-spinning technique. The fabric structure was diversified by the feeding modes of weft yarn into a crochet-knitting machine. The twist number of complex yarns was optimized by tensile tenacity, twist contraction, and hairiness, and analysis showed that twisting at 12 twists per inch produced the highest tensile tenacity and appropriate twist contraction and hairiness. Comfort evaluation showed that the elastic composite fabrics with BC weft yarns exhibited higher water–vapor transmission rate and air permeability, reaching 876 g/m2∙ day and 73.2 cm3/s/cm2, respectively. Three structures of composite fabric with various weft yarns had >0.85 ε far-infrared emissivity and 350–420 counts/cm3 anion amount. The prepared elastic warp-knitted fabrics can provide a comfortable, dry, and breathable environment to the wearer and can thus be applied as health-care textiles in the future.
Ricci Flow of Warped Product Metrics with Positive Isotropic Curvature on $S^{p+1}× S^1$
Indian Academy of Sciences (India)
H A Gururaja
2012-11-01
We study the asymptotic behaviour of the ODE associated to the evolution of curvature operator in the Ricci flow of a doubly warped product metric on $S^{p+1}× S^1$ with positive isotropic curvature.
G\\"odel, warped AdS$_3$ and flows from $\\mathcal{N} = (0,2)$ SCFTs
Colgáin, Eoin Ó
2015-01-01
We present all timelike supersymmetric solutions to 3D U(1)$^3$ gauged supergravity, a known consistent truncation of string theory. We uncover a rich vacuum structure, including an infinite class of new timelike (G\\"odel) and spacelike warped AdS$_3$ critical points. We outline the construction of holographic flows interpolating between AdS$_3$ and warped AdS$_3$ critical points.
Method and apparatus for sizing and separating warp yarns using acoustical energy
Energy Technology Data Exchange (ETDEWEB)
Sheen, S.H.; Chien, H.T.; Raptis, A.C.; Kupperman, D.S.
1998-05-19
A slashing process is disclosed for preparing warp yarns for weaving operations including the steps of sizing and/or desizing the yarns in an acoustic resonance box and separating the yarns with a leasing apparatus comprised of a set of acoustically agitated lease rods. The sizing step includes immersing the yarns in a size solution contained in an acoustic resonance box. Acoustic transducers are positioned against the exterior of the box for generating an acoustic pressure field within the size solution. Ultrasonic waves that result from the acoustic pressure field continuously agitate the size solution to effect greater mixing and more uniform application and penetration of the size onto the yarns. The sized yarns are then separated by passing the warp yarns over and under lease rods. Electroacoustic transducers generate acoustic waves along the longitudinal axis of the lease rods, creating a shearing motion on the surface of the rods for splitting the yarns. 2 figs.
Diphoton signal via Chern-Simons interaction in a warped geometry scenario
Chakrabarty, Nabarun; Mukhopadhyaya, Biswarup; SenGupta, Soumitra
2017-01-01
The Kalb-Ramond field, identifiable with bulk torsion in a five-dimensional Randall Sundrum (RS) scenario, has Chern-Simons interactions with gauge bosons, from the requirement of gauge anomaly cancellation. Its lowest Kaluza Klein (KK) mode on the visible 3-brane can be identified with a spin-0 C P -odd field, namely, the axion. By virtue of the warped geometry and Chern-Simons couplings, this axion has unsuppressed interactions with gauge bosons in contrast to ultra-suppressed interactions with fermions. The ensuing dynamics can lead to a peak in the diphoton spectrum, which could be observed at the LHC, subject to the prominence of the signal. Moreover, the results can be numerically justified when the warp factor is precisely in the range required for stabilization of the electroweak scale.
Li, Yan-Rong; Cheng, Cheng; Qiu, Jie
2015-01-01
Warped accretion disks have attracted intensive attention because of their critical role on shaping the spin of supermassive massive black holes (SMBHs) through the Bardeen-Petterson effect, a general relativistic effect that leads to final alignments or anti-alignments between black holes and warped accretion disks. We study such alignment processes by explicitly taking into account the finite sizes of accretion disks and the episodic lifetimes of AGNs that delineate the duration of gas fueling onto accretion disks. We employ an approximate global model to simulate the evolution of accretion disks, allowing to determine the gravitomagnetic torque that drives the alignments in a quite simple way. We then track down the evolutionary paths for mass and spin of black holes both in a single activity episode and over a series of episodes. Given with randomly and isotropically oriented gas fueling over episodes, we calculate the spin evolution with different episodic lifetimes and find that it is quite sensitive to...
Moisture Comfort and Antibacterial Properties of Elastic Warp-Knitted Fabrics
Directory of Open Access Journals (Sweden)
Yu Zhi-Cai
2015-03-01
Full Text Available Multifunction elastic warp-knitted fabrics were fabricated on a crochet machine with the use of metal composite yarns/viscose yarn and bamboo polyester/ crisscross-section polyester hybrid yarns as the front face and back face of the knitted fabric structure, respectively. We investigated the effect of the blend ratio of bamboo charcoal/ crisscross-section polyester multiply yarns on the fabric's moisture comfort properties, such as water vapour transmission (WVT, water evaporation rate (WER, and water absorbency. The results showed that blending ratio significantly influenced WVT and WER. Moreover, antibacterial activity of the elastic warp- knitted fabric was tested against Staphylococcus aureus and Escherichia coli in accordance with AATCC 90-2011. Finally, the extension- stress value curves were used to analyse the elastic stretching property, and the fabric exhibited greater breaking elongation and lower stress value in the walewise than in the weft direction.
Directory of Open Access Journals (Sweden)
Aditya Sukmana Putra
2015-03-01
Full Text Available Dalam sistem komunikasi nirkabel, khususnya pada dunia komunikasi taktis atau militer, salah satu yang harus dihadapi adalah gangguan jamming.Salah satu sistem yang dapat mengatasi masalah tersebut adalah Direct Sequence Spread Spectrum (DSSS dimana informasi akan dikalikan secara langsung dengan pseudo-noise sequence yang mempunyai laju chip jauh lebih besar.Sistem ini dapat diimplementasikan pada Wireless Open-Access Research Platform (WARP yang merupakan salah satu dari jenis Software Define Radio (SDR.Modul WARP mampu diprogram secara langsung dengan software MATLAB.Kinerja sistem terbaik didapatkan ketika daya sinyal jamming lebih kecil atau sama dengan daya sinyal carrier sistem DSSS. Pada Single Tone Jamming (STJ sistem akan mencapai nilai BER 10E-3 saat daya sinyal jamming 125 % dari daya sinyal sistem DSSS, sedangkan pada Multi Tone Jamming (MTJ sistem akan mencapai BER 10E-3 saat daya sinyal jamming 100 % dari daya sistem DSSS.
Stability of warped AdS3 black holes in Topologically Massive Gravity under scalar perturbations
Ferreira, Hugo R C
2013-01-01
We demonstrate that the warped AdS3 black hole solutions of Topologically Massive Gravity are classically stable against massive scalar field perturbations by analysing the quasinormal and bound state modes of the scalar field. In particular, it is found that although classical superradiance is present it does not give rise to superradiant instabilities. The stability is shown to persist even when the black hole is enclosed by a stationary mirror with Dirichlet boundary conditions. This is a surprising result in view of the similarity between the causal structure of the warped AdS3 black hole and the Kerr spacetime in 3+1 dimensions. This work provides the foundations for the study of quantum field theory in this spacetime.
The WArP Experiment: A Double-Phase Argon Detector for Dark Matter Searches
Directory of Open Access Journals (Sweden)
Andrea Zani
2014-01-01
Full Text Available Cryogenic noble liquids emerged in the previous decade as one of the best media to perform WIMP dark matter searches, in particular due to the possibility to scale detector volumes to multiton sizes. The WArP experiment was then developed as one of the first to implement the idea of coupling Argon in liquid and gas phase, in order to discriminate β/γ-interactions from nuclear recoils and then achieve reliable background rejection. Since its construction, other projects spawned, employing Argon and Xenon and following its steps. The WArP 100l detector was assembled in 2008 at the Gran Sasso National Laboratories (LNGS, as the final step of a years-long R&D programme, aimed at characterising the technology of Argon in double phase for dark matter detection. Though it never actually performed a physics run, a technical run was taken in 2011, to characterise the detector response.
Low-scale gravity mediation in warped extra dimension and collider phenomenology on hidden sector
Indian Academy of Sciences (India)
H Itoh; N Okada; T Yamashita
2007-11-01
We propose a new scenario of gravity-mediated supersymmetry breaking (gravity mediation) in a supersymmetric Randall-Sundrum model, where the gravity mediation takes place at a low scale due to the warped metric. We investigate collider phenomenology involving the hidden sector field, and find a possibility that the hidden sector field can be produced at the LHC and the ILC. The hidden sector may no longer be hidden.
A non-minimally coupled quintom dark energy model on the warped DGP brane
Energy Technology Data Exchange (ETDEWEB)
Nozari, K; Azizi, T [Department of Physics, Faculty of Basic Sciences, University of Mazandaran, PO Box 47416-95447, Babolsar (Iran, Islamic Republic of); Setare, M R [Department of Science, University of Kurdistan, Pasdaran Ave, Sanandaj (Iran, Islamic Republic of); Behrouz, N [Department of Physics, Payam-e Nour University, PO Box 919, Mashad (Iran, Islamic Republic of)], E-mail: knozari@umz.ac.ir, E-mail: rezakord@ipm.ir, E-mail: t.azizi@umz.ac.ir
2009-08-15
We construct a quintom dark energy model with two non-minimally coupled scalar fields, one quintessence and the other phantom field, confined to the warped Dvali-Gabadadze-Porrati (DGP) brane. We show that this model accounts for crossing of the phantom divide line in appropriate subspaces of the model parameter space. This crossing occurs for both normal and self-accelerating branches of this DGP-inspired setup.
2014-01-01
This thesis examines the warp weighted loom during the Anglo-Saxon and Viking eras in England through archaeological, linguistic, and art evidence, supported by similar information about the loom from Northern Continental Europe. Some evidence from other parts of the world where this specific type of loom was used is also included for clarity. In order to further understanding of the possible functioning and abilities of the loom, modern individuals with experience weaving with this early med...
Influence of Warp Yarn Tension on Cotton Greige and Dyed Woven Fabric Prosperities
Uzma Syed; Rafique Ahmed Jhatial
2013-01-01
Fabric properties such as pilling and abrasion resistance and tensile strength vary when greige fabric is processed further. The quality of dyed fabric depends on the quality of greige fabric. Cotton Plain and Twill weave fabrics were woven at three different warp yarn tension and then dyed using monochlorotriazine, Drimerene Red Cl-5B dye gives difference in fabric properties. The ASTM, American International Standards were used to determine the greige and dyed fabric properties. It has been...
Two-step flash light sintering of copper nanoparticle ink to remove substrate warping
Energy Technology Data Exchange (ETDEWEB)
Ryu, Chung-Hyeon; Joo, Sung-Jun [Department of Mechanical Convergence Engineering, Hanyang University, Haengdang-dong, Seongdong-gu, Seoul 133-791 (Korea, Republic of); Kim, Hak-Sung, E-mail: kima@hanyang.ac.kr [Department of Mechanical Convergence Engineering, Hanyang University, Haengdang-dong, Seongdong-gu, Seoul 133-791 (Korea, Republic of); Institute of Nano Science and Technology, Hanyang University, Seoul, 133-791 (Korea, Republic of)
2016-10-30
Highlights: • We performed the two-step flash light sintering for copper nanoparticle ink to remove substrate warping. • 12 J/cm{sup 2} of preheating and 7 J/cm{sup 2} of main sintering energies were determined as optimum conditions to sinter the copper nanoparticle ink. • The resistivity of two-step sintered copper nanoparticle ink was 3.81 μΩ cm with 5B adhesion level, 2.3 times greater than that of bulk copper. • The two-step sintered case showed a high conductivity without any substrate warping. - Abstract: A two-step flash light sintering process was devised to reduce the warping of polymer substrates during the sintering of copper nanoparticle ink. To determine the optimum sintering conditions of the copper nanoparticle ink, the flash light irradiation conditions (pulse power, pulse number, on-time, and off-time) were varied and optimized. In order to monitor the flash light sintering process, in situ resistance and temperature monitoring of copper nanoink were conducted during the flash light sintering process. Also, a transient heat transfer analysis was performed by using the finite-element program ABAQUS to predict the temperature changes of copper nanoink and polymer substrate. The microstructures of the sintered copper nanoink films were analyzed by scanning electron microscopy. Additionally, an X-ray diffraction and Fourier transform infrared spectroscopy were used to characterize the crystal phase change of the sintered copper nanoparticles. The resulting two-step flash light sintered copper nanoink films exhibited a low resistivity (3.81 μΩ cm, 2.3 times of that of bulk copper) and 5B level of adhesion strength without warping of the polymer substrate.
Warped anti-de Sitter in 3d (2,0) Supergravity
Moutsopoulos, George
2016-01-01
We comment on the ubiquity of the so-called warped anti-de Sitter spacetimes in three-dimensional (2,0) supergravity theory. By using isometry-invariant tensors and simple counting, we prove their existence for arbitrary $(2,0)$ supergravity models suitably defined close to a minimal model. We also analyze their offshell supersymmetry and the supersymmetry of two geometric orbifolds.
A Geometric Model of Multiaxial Warp-knitted Preform for Composite Reinforcement
Institute of Scientific and Technical Information of China (English)
周荣星; 李炜; 陈南梁; 冯勋伟
2003-01-01
A new geometric model of Multiaxial Warp-Knitted (MWK) performs, which is based on the experimental observations and analysis of basic stitch, is developed to relate the geometric parameters and process variables. The fiber volume fraction and fibre orientation of MWK reinforced composites are described in terms of structural and processing parameters in the model. And this model provides a basis for the prediction of mechanical behavior of the MWK reinforced composites.
2015-03-01
and channel estimation. The STS and LTS sequences used in the preamble are the same as what has been defined in the IEEE 802.11 WiFi standard. However...developed with 64 sub carriers and have guards and pilots as comparable to the 802.11a WiFi standard. An eavesdropper/interferer (ExJx) is used to...14 2.2.4 WARP Channel State Information (CSI) . . . . . . . . . . . . . . . . . . . 14 2.3 Signal feature estimation
Radiation-Driven Warping of Circumbinary Disks Around Eccentric Young Star Binaries
Hayasaki, Kimitake; Okazaki, Atsuo T; Jung, Taehyun; Zhao, Guangyao; Naito, Tsuguya
2014-01-01
We study a warping instability of a geometrically thin, non-self-gravitating, circumbinary disk around young binary stars on an eccentric orbit. Such a disk is subject to both the tidal torques due to a time-dependent binary potential and the radiative torques due to radiation emitted from each star. The tilt angle between the circumbinary disk plane and the binary orbital plane is assumed to be very small. We find that there is a radius within/beyond which the circumbinary disk is unstable to radiation-driven warping, depending on the disk density and temperature gradient indices. This marginally stable warping radius is very sensitive to viscosity parameters, a fiducial disk radius and the temperature measured there, the stellar luminosity, and the disk surface density at a radius where the disk changes from the optically thick to thin for the irradiation from the central stars. On the other hand, it is insensitive to the orbital eccentricity and binary irradiation parameter, which is a function of the bina...
Evolution of warped and twisted accretion discs in close binary systems
Fragner, Moritz
2009-01-01
We aim to examine the detailed disc structure that arises in a misaligned binary system as a function of the disc aspect ratio h, viscosity parameter alpha, disc outer radius R, and binary inclination angle gamma_F. We also aim to examine the conditions that lead to an inclined disc being disrupted by strong differential precession. We use a grid-based hydrodynamic code to perform 3D simulations. This code has a relatively low numerical viscosity compared with the SPH schemes that have been used previously to study inclined discs. This allows the influence of viscosity on the disc evolution to be tightly controlled. We find that for thick discs (h=0.05) with low alpha, efficient warp communication in the discs allows them to precess as rigid bodies with very little warping or twisting. Such discs are observed to align with the binary orbit plane on the viscous evolution time. Thinner discs with higher viscosity, in which warp communication is less efficient, develop significant twists before achieving a state...
Wave-like warp propagation in circumbinary discs I. Analytic theory and numerical simulations
Facchini, Stefano; Price, Daniel J
2013-01-01
In this paper we analyse the propagation of warps in protostellar circumbinary discs. We use these systems as a test environment in which to study warp propagation in the bending-wave regime, with the addition of an external torque due to the binary gravitational potential. In particular, we want to test the linear regime, for which an analytic theory has been developed. In order to do so, we first compute analytically the steady state shape of an inviscid disc subject to the binary torques. The steady state tilt is a monotonically increasing function of radius. In the absence of viscosity, the disc does not present any twist. Then, we compare the time-dependent evolution of the warped disc calculated via the known linearised equations both with the analytic solutions and with full 3D numerical simulations, which have been performed with the PHANTOM SPH code using 2 million particles. We find a good agreement both in the tilt and in the phase evolution for small inclinations, even at very low viscosities. Mor...
Galactic disc warps due to intergalactic accretion flows onto the disc
López-Corredoira, M; Beckman, J E
2007-01-01
The accretion of the intergalactic medium onto the gaseous disc is used to explain the generation of galactic warps. A cup-shaped distortion is expected, due to the transmission of the linear momentum; but, this effect is small for most incident inflow angles and the predominant effect turns out to be the transmission of angular momentum, i.e. a torque giving an integral-sign shaped warp. The torque produced by a flow of velocity ~100 km/s and baryon density ~10^{-25} kg/m^3, which is within the possible values for the intergalactic medium, is enough to generate the observed warps and this mechanism offers quite a plausible explanation. The inferred rate of infall of matter, ~1 M_sun/yr, to the Galactic disc that this theory predicts agrees with the quantitative predictions of chemical evolution resolving key issues, notably the G-dwarf problem. Sanchez-Salcedo (2006) suggests that this mechanism is not plausible because it would produce a dependence of the scaleheight of the disc with the Galactocentric azim...
Fu, Shangchen; Shi, Lihua; Zhou, Yinghui; Cai, Jian
2014-12-01
The damage localization accuracy of a Lamb wave detection method is greatly influenced by the multi-mode character and the dispersion effect of Lamb waves. Warped frequency transform (WFT) with a warping function derived from the frequency-dependent phase velocity can be used to suppress the dispersion. Step-pulse excitation is adopted in this paper and the transfer function of the propagation path is extracted from the step-pulse response. WFT is then used to compensate the transfer function, and the compensation of the narrowband signal is realized by convolution of the ideal narrowband burst signal with the compensated transfer function. Considering that wavenumber is a key parameter in designing the warping function for compensation, we presented a method in this paper to calculate the wavenumber directly from the measured signal. This method uses the phase response to estimate the curve of wavenumber. The WFT method is then combined with the delay-and-sum Lamb wave imaging method to improve the imaging resolution. A comparison with traditional delay-and-sum method and time-reversal method verifies the effect of this method in improving the damage localization results. It is shown that the proposed method leverages dispersion to enable good performance in the presence of multiple modes.
Kaluza-Klein graviton phenomenology for warped compactifications, and the 750 GeV diphoton excess
Giddings, Steven B.; Zhang, Hao
2016-06-01
A generic prediction of scenarios with extra dimensions accessible in TeV-scale collisions is the existence of Kaluza-Klein excitations of the graviton. For a broad class of strongly warped scenarios one expects to initially find an isolated resonance, whose phenomenology in the simplest cases is described by a simplified model with two parameters, its mass, and a constant Λ with units of mass parametrizing its coupling to the Standard Model stress tensor. These parameters are in turn determined by the geometrical configuration of the warped compactification. We explore the possibility that the 750 GeV excess recently seen in 13 TeV data at ATLAS and CMS could be such a warped Kaluza-Klein graviton, and find a best-fit value Λ ≈60 TeV . We find that while there is some tension between this interpretation and data from 8 TeV and from the dilepton channel at 13 TeV, it is not strongly excluded. However, in the simplest scenarios of this kind, such a signal should soon become apparent in both diphoton and dilepton channels.
Bulk photons in Asymmetrically Warped Space-times and Non-trivial Vacuum Refractive Index
Farakos, K; Pasipoularides, P
2009-01-01
We consider asymmetrically warped brane models, or equivalently brane models where the background metric is characterized by different time and space warp factors. The main feature of these models is that 4D Lorentz symmetry is violated for fields which propagate in the bulk, such as gravitons. In this paper we examine the case of bulk photons in asymmetrically warped brane models. Although our results are general, we examine here two specific but characteristic solutions: 1) AdS-Schwarzschild 5D Black Hole solution and 2) AdS-Reissner Nordstrom 5D Black Hole solution. We show that the standard Lorentz invariant dispersion relation for 4D photons is corrected by nonlinear terms which lead to an Energy-dependent speed of light. Specifically, we obtain a sub-luminous Energy-dependent refractive index of the form n_{eff}(omega)=1+c_G omega^2, where omega is the energy of the photon, and the factor c_G is always positive and depends on the free parameters of the model. Finally, comparing the results with recent d...
Spectrum warping based on sub-glottal resonances in speaker-independent speech recognition
Institute of Scientific and Technical Information of China (English)
HOU Limin; HUANG Zhenhua; XIE Juanmin
2011-01-01
To reduce degradation in speech recognition due to varied characteristics of different speakers, a method of perceptual frequency warping based on subglottal resonances for speaker normalization is proposed. The warping factor is extracted from the second subglottal resonance using acoustic coupling between subglottis and vocal tract. The second subglottal resonance is independent of the speech content, which reflects the speaker characteristics more than the third formant. The perceptual minimum variation distortionless response （PMVDR） coefficient is normalized, which is more robust and has better anti-noise capability than MFCC. The normalized coefficients are used in the speech-mode training and speech recognition. Experiments show that the word error rate, as compared with MFCC and the spectrum warping by the third formant, decreases by 4% and 3% respectively in clean speech recognition, and by 9% and 5% respectively in a noisy environment. The results indicate that the proposed method can improve the word recognition accuracy in a speaker-independent recognition system.
Kaluza-Klein graviton phenomenology for warped compactifications, and the 750 GeV diphoton excess
Giddings, Steven B
2016-01-01
A generic prediction of scenarios with extra dimensions accessible in TeV-scale collisions is the existence of Kaluza-Klein excitations of the graviton. For a broad class of strongly-warped scenarios one expects to initially find an isolated resonance, whose phenomenology in the simplest cases is described by a simplified model with two parameters, its mass, and a constant $\\Lambda$ with units of mass parameterizing its coupling to the Standard Model stress tensor. These parameters are in turn determined by the geometrical configuration of the warped compactification. We explore the possibility that the 750 GeV excess recently seen in 13 TeV data at ATLAS and CMS could be such a warped Kaluza-Klein graviton, and find a best-fit value $\\Lambda\\approx 60$ TeV. We find that while there is some tension between this interpretation and data from 8 TeV and from the dilepton channel at 13 TeV, it is not strongly excluded. However, in the simplest scenarios of this kind, such a signal should soon become apparent in bo...
An Unbiased Survey for Molecular Clouds in the Southern Galactic Warp
Nakagawa, M; Mizuno, A; Fukui, Y; Nakagawa, Masanori
2005-01-01
We have made an unbiased survey for molecular clouds in the Galactic Warp. This survey, covering an area of 56 square degrees at l = 252 deg to 266 deg and b = -5 deg to -1 deg, has revealed 70 molecular clouds, while only 6 clouds were previously known in the region. The number of molecular clouds is, then, an order of magnitude greater than previously known in this sector at R > 14.5 kpc. The mass of the clouds is in a range from 7.8x10(2) Mo to 8.4x10(4) Mo, significantly less than the most massive giant molecular clouds in the inner disk, ~10(6) Mo, while the cloud mass spectrum characterized by a power law is basically similar to other parts of the Galaxy. The X factor, N(H2)/Wco(12CO), derived from the molecular clouds in the Warp is estimated to be 3.5(+/-1.8) times larger than that in the inner disk. The total molecular mass in the Warp is estimated as 7.3x10(5) Mo, and total mass in the far-outer Galaxy (R > 14.5 kpc) can be estimated as 2x10(7) Mo. The spatial correlation between the CO and HI distr...
Levin, David; Dey, Damini; Slomka, Piotr
2005-04-01
We have implemented two hardware accelerated Thin Plate Spline (TPS) warping algorithms. The first algorithm is a hardware-software approach (HW-TPS) that uses OpenGL Vertex Shaders to perform a grid warp. The second is a Graphics Processor based approach (GPU-TPS) that uses the OpenGL Shading Language to perform all warping calculations on the GPU. Comparison with a software TPS algorithm was used to gauge the speed and quality of both hardware algorithms. Quality was analyzed visually and using the Sum of Absolute Difference (SAD) similarity metric. Warping was performed using 92 user-defined displacement vectors for 512x512x173 serial lung CT studies, matching normal-breathing and deep-inspiration scans. On a Xeon 2.2 Ghz machine with an ATI Radeon 9800XT GPU the GPU-TPS required 26.1 seconds to perform a per-voxel warp compared to 148.2 seconds for the software algorithm. The HW-TPS needed 1.63 seconds to warp the same study while the GPU-TPS required 1.94 seconds and the software grid transform required 22.8 seconds. The SAD values calculated between the outputs of each algorithm and the target CT volume were 15.2%, 15.4% and 15.5% for the HW-TPS, GPU-TPS and both software algorithms respectively. The computing power of ubiquitous 3D graphics cards can be exploited in medical image processing to provide order of magnitude acceleration of nonlinear warping algorithms without sacrificing output quality.
Institute of Scientific and Technical Information of China (English)
诸德超; 邓忠民; 王荇卫
2001-01-01
In the present paper, a series of hierarchical warping functions is developed to analyze the static and dynamic problems of thin walled composite laminated helicopter rotors composed of several layers with single closed cell. This ethod is the development and extension of the traditional constrained warping theory of thin walled metallic beams, which had been proved very successful since 1940s. The warping distribution along the perimeter of each layer is expanded into a series of successively corrective warping functions with the traditional warping function caused by free torsion or free bending as the first term, and is assumed to be piecewise linear along the thickness direction of layers. The governing equations are derived based upon the variational principle of minimum potential energy for static analysis and Rayleigh Quotient for free vibration analysis. Then the hierarchical finite element method is introduced to form a numerical algorithm. Both static and natural vibration problems of sample box beams are analyzed with the present method to show the main mechanical behavior of the thin walled composite laminated helicopter rotor.
Vacuum $ f(R)$ thick brane solution with a Gaussian warp function
Hashemi, S Sedigheh
2016-01-01
This work deals with $f(R)$ modified gravity in five dimensional space-time. The Gaussian thick brane is shown to be an exact solution in the frame work of $f(R)$ gravity in five dimensions with a bulk cosmological constant. Response of the brane to gravitational fluctuations and concordance with the Starobinsky model is addressed. It is shown that the matter which supports the Starobinsky $f(R)$ solution with the background geometry being flat FLRW with a Gaussian warp function, behaves like a radiation dominated era of universe, gradually changing to a dark energy dominated era.
Warped Wigner-Hough Transform for Defect Reflection Enhancement in Ultrasonic Guided Wave Monitoring
Directory of Open Access Journals (Sweden)
Luca De Marchi
2012-01-01
Full Text Available To improve the defect detectability of Lamb wave inspection systems, the application of nonlinear signal processing was investigated. The approach is based on a Warped Frequency Transform (WFT to compensate the dispersive behavior of ultrasonic guided waves, followed by a Wigner-Ville time-frequency analysis and the Hough Transform to further improve localization accuracy. As a result, an automatic detection procedure to locate defect-induced reflections was demonstrated and successfully tested by analyzing numerically simulated Lamb waves propagating in an aluminum plate. The proposed method is suitable for defect detection and can be easily implemented for real-world structural health monitoring applications.
Study of Confinement/Deconfinement Transition in AdS/QCD with Generalized Warp Factors
Directory of Open Access Journals (Sweden)
Shobhit Sachan
2014-01-01
Full Text Available We study analytical solutions of charged black holes and thermally charged AdS with generalized warped factors in Einstein-Maxwell-Dilaton system. We calculate Euclidean action for charged AdS and thermally charged AdS. The actions in both backgrounds are regularized by the method of background subtraction. The study of phase transition between charged black hole and thermally charged AdS gives an insight into the confinement/deconfinement transition. The plots of grand potential versus temperature and chemical potential versus transition temperature are obtained.
Hawking Radiation of Massive Vector Particles From Warped AdS$_{\\text{3}}$ Black Hole
Gursel, H
2015-01-01
Hawking radiation (HR) of massive vector particles from a rotating Warped Anti-de Sitter black hole in 2+1 dimensions (WAdS$_{\\text{3}}$BH) is studied in detail. The quantum tunneling approach with the Hamilton-Jacobi method (HJM) is applied in the Proca equation (PE), and we show that the radial function yields the tunneling rate of the outgoing particles. Comparing the result obtained with the Boltzmann factor, we satisfactorly reproduce the Hawking temperature (HT) of the WAdS$_{\\text{3}}$BH.
Linearization of a warped $f(R)$ theory in the higher-order frame
Zhong, Yuan
2016-01-01
The linearization of a type of $f(R)$ gravity is studied directly in the higher-order frame for an arbitrary five-dimensional warped space-time background. The quadratic actions of the normal modes of the scalar, vector and tensor perturbations are derived, and compared to those obtained in the Einstein frame. We find that the corresponding quadratic actions are equivalent. From the point of view of the higher-order frame, the best gauge choice is the curvature gauge, under which the linear perturbation of the scalar curvature is zero, and all the perturbation equations reduce to second order.
The impact of emerging technology on nursing care: warp speed ahead.
Huston, Carol
2013-05-31
While myriad forces are changing the face of contemporary healthcare, one could argue that nothing will change the way nursing is practiced more than current advances in technology. Indeed, technology is changing the world at warp speed and nowhere is this more evident than in healthcare settings. This article identifies seven emerging technologies that will change the practice of nursing; three skill sets nurses will need to develop to acquire, use, and integrate these emerging technologies; and four challenges nurse leaders will face in integrating this new technology.
Modeling laser-driven electron acceleration using WARP with Fourier decomposition
Energy Technology Data Exchange (ETDEWEB)
Lee, P., E-mail: patrick.lee@u-psud.fr [LPGP, CNRS, Univ. Paris-Sud, Université Paris-Saclay, 91405 Orsay (France); Audet, T.L. [LPGP, CNRS, Univ. Paris-Sud, Université Paris-Saclay, 91405 Orsay (France); Lehe, R.; Vay, J.-L. [Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Maynard, G.; Cros, B. [LPGP, CNRS, Univ. Paris-Sud, Université Paris-Saclay, 91405 Orsay (France)
2016-09-01
WARP is used with the recent implementation of the Fourier decomposition algorithm to model laser-driven electron acceleration in plasmas. Simulations were carried out to analyze the experimental results obtained on ionization-induced injection in a gas cell. The simulated results are in good agreement with the experimental ones, confirming the ability of the code to take into account the physics of electron injection and reduce calculation time. We present a detailed analysis of the laser propagation, the plasma wave generation and the electron beam dynamics.
Diboson resonances within a custodially protected warped extra-dimensional scenario
Angelescu, Andrei; Moreau, Grégory; Richard, François
2015-01-01
We propose an interpretation of the diboson excess recently observed by the ATLAS and CMS collaborations in terms of Kaluza-Klein excitations of electroweak gauge bosons stemming from a realization of a warped extra-dimensional model that is protected by a custodial symmetry. Besides accounting for the LHC diboson data, this scenario also leads to an explanation of the anomalies that have been observed in the measurements of the forward-backward asymmetries for bottom quarks at LEP and top quarks at the Tevatron.
Application of Bi-axial Warp Knitted Structures in Concrete Constructions
Institute of Scientific and Technical Information of China (English)
李炜; 陈南梁
2001-01-01
The warp knitted bi-axial directionally oriented structure (D. O. S. ) reinforcement substrates applied to building construction are discussed in comparison to woven fabrics. One of usage barriers of reinforced cement with gloss-grid is its sensitivity to alkali existed in the cement which will lead to the reduction of its service-life. The tests show that the treatment by sol-gel method to protect the composite from alkali corrosion is effective. Then two formulae of sol-gel solution are also recommended here for application.
Sharma, Vikas; Parey, Anand
2017-02-01
In the purview of fluctuating speeds, gear fault diagnosis is challenging due to dynamic behavior of forces. Various industrial applications employing gearbox which operate under fluctuating speed conditions. For diagnostics of a gearbox, various vibrations based signal processing techniques viz FFT, time synchronous averaging and time-frequency based wavelet transform, etc. are majorly employed. Most of the time, theories about data or computational complexity limits the use of these methods. In order to perform fault diagnosis of a gearbox for fluctuating speeds, frequency domain averaging (FDA) of intrinsic mode functions (IMFs) after their dynamic time warping (DTW) has been done in this paper. This will not only attenuate the effect of fluctuating speeds but will also extract the weak fault feature those masked in vibration signal. Experimentally signals were acquired from Drivetrain Diagnostic Simulator for different gear health conditions i.e., healthy pinion, pinion with tooth crack, chipped tooth and missing tooth and were analyzed for the different fluctuating profiles of speed. Kurtosis was calculated for warped IMFs before DTW and after DTW of the acquired vibration signals. Later on, the application of FDA highlights the fault frequencies present in the FFT of faulty gears. The result suggests that proposed approach is more effective towards the fault diagnosing with fluctuating speed.
A Solvable Model for Fermion masses on a warped 6D world with the extra 2D sphere
Kokado, Akira
2014-01-01
In a warped 6D world with an extra 2-dimensional sphere, we propose an exactly solvable model for fermion masses with zero mode. The warp factor is given by $\\phi (\\theta ,\\varphi )=\\sin{\\theta }\\cos{\\varphi }$, which is a solution to the 6D Einstein equation with the bulk cosmological constant $\\Lambda $ and the energy-momentum tensor of the bulk matter fields. Our model provides another possibility of obtaining fermion zero mode, rather than traditional model based on Dirac's monopole.
Geometry and supersymmetry of heterotic warped flux AdS backgrounds
Beck, S.; Gutowski, J.; Papadopoulos, G.
2015-07-01
We classify the geometries of the most general warped, flux AdS backgrounds of heterotic supergravity up to two loop order in sigma model perturbation theory. We show under some mild assumptions that there are no AdS n backgrounds with n ≠ 3. Moreover the warp factor of AdS3 backgrounds is constant, the geometry is a product AdS 3 × M 7 and such solutions preserve, 2, 4, 6 and 8 supersymmetries. The geometry of M 7 has been specified in all cases. For 2 supersymmetries, it has been found that M 7 admits a suitably restricted G 2 structure. For 4 supersymmetries, M 7 has an SU(3) structure and can be described locally as a circle fibration over a 6-dimensional KT manifold. For 6 and 8 supersymmetries, M 7 has an SU(2) structure and can be described locally as a S 3 fibration over a 4-dimensional manifold which either has an anti-self dual Weyl tensor or a hyper-Kähler structure, respectively. We also demonstrate a new Lichnerowicz type theorem in the presence of α' corrections.
Novel methods in the Particle-In-Cell accelerator Code-Framework Warp
Energy Technology Data Exchange (ETDEWEB)
Vay, J-L [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Grote, D. P. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Cohen, R. H. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Friedman, A. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
2012-12-26
The Particle-In-Cell (PIC) Code-Framework Warp is being developed by the Heavy Ion Fusion Science Virtual National Laboratory (HIFS-VNL) to guide the development of accelerators that can deliver beams suitable for high-energy density experiments and implosion of inertial fusion capsules. It is also applied in various areas outside the Heavy Ion Fusion program to the study and design of existing and next-generation high-energy accelerators, including the study of electron cloud effects and laser wakefield acceleration for example. This study presents an overview of Warp's capabilities, summarizing recent original numerical methods that were developed by the HIFS-VNL (including PIC with adaptive mesh refinement, a large-timestep 'drift-Lorentz' mover for arbitrarily magnetized species, a relativistic Lorentz invariant leapfrog particle pusher, simulations in Lorentz-boosted frames, an electromagnetic solver with tunable numerical dispersion and efficient stride-based digital filtering), with special emphasis on the description of the mesh refinement capability. In addition, selected examples of the applications of the methods to the abovementioned fields are given.
Wave-like warp propagation in circumbinary discs II. Application to KH 15D
Lodato, Giuseppe
2013-01-01
KH 15D is a protostellar binary system that shows a peculiar light curve. In order to model it, a narrow circumbinary precessing disc has been invoked, but a proper dynamical model has never been developed. In this paper, we analytically address the issue of whether such a disc can rigidly precess around KH 15D, and we relate the precessional period to the main parameters of the system. Then, we simulate the disc's dynamics by using a 1D model developed in a companion paper, such that the warp propagates into the disc as a bending wave, which is expected to be the case for protostellar discs. The validity of such an approach has been confirmed by comparing its results with full 3D SPH simulations on extended discs. In the present case, we use this 1D code to model the propagation of the warp in a narrow disc. If the inner truncation radius of the disc is set by the binary tidal torques at {\\sim} 1 AU, we find that the disc should extend out to 6-10 AU (depending on the models), and is therefore wider than pre...
Gauge vector field localization on 3-brane placed in a warped transverse resolved conifold
Costa, F W V; Almeida, C A S
2013-01-01
We have investigated the features of the gauge vector field in a braneworld scenario built as a warped product between a 3-brane and a 2-cycle of the resolved conifold. This scenario allowed us to study how the gauge field behaves when the transverse manifold evolves upon a geometric flow that controls the singularity at the origin. Besides, since the transverse manifold has a cylindrical symmetry according to the 3-brane, this geometry can be regarded as a near brane correction of the string-like branes. Indeed, by means of a new warp function and the angular metric component of the resolved conifold, the braneworld can exhibit a conical form near the origin as well as a regular behavior in that region. The analysis of the gauge field in this background has been carried out for the s-wave state and a normalizable massless mode was found. For the massive modes, the resolution parameter avoids an infinite well on the brane and controls the depth of the well and the high of the barrier around the brane. The mas...
Mechanical Properties Of 3D-Structure Composites Based On Warp-Knitted Spacer Fabrics
Directory of Open Access Journals (Sweden)
Chen Si
2015-06-01
Full Text Available In this paper, the mechanical properties (compression and impact behaviours of three-dimension structure (3D-structure composites based on warp-knitted spacer fabrics have been thoroughly investigated. In order to discuss the effect of fabric structural parameters on the mechanical performance of composites, six different types of warp-knitted spacer fabrics having different structural parameters (such as outer layer structure, diameter of spacer yarn, spacer yarn inclination angle and thickness were involved for comparison study. The 3D-structure composites were fabricated based on a flexible polyurethane foam. The produced composites were characterised for compression and impact properties. The findings obtained indicate that the fabric structural parameters have strong influence on the compression and impact responses of 3D-structure composites. Additionally, the impact test carried out on the 3D-structure composites shows that the impact loads do not affect the integrity of composite structure. All the results reveal that the product exhibits promising mechanical performance and its service life can be sustained.
Keck/NIRC2 Imaging of the Warped, Asymmetric Debris Disk around HD 32297
Currie, Thayne; Debes, John; Plavchan, Peter; Kuchner, Marc; Jang-Condell, Hannah; Wilner, David; Andrews, Sean; Kraus, Adam; Dahm, Scott; Robitaille, Thomas
2012-01-01
We present Keck/NIRC2 $K_{s}$ band high-contrast coronagraphic imaging of the luminous debris disk around the nearby, young A star HD 32297 resolved at a projected separation of $r$ = 0.3-2.5\\arcsec{} ($\\approx$ 35-280 AU). The disk is highly warped to the north and exhibits a complex, "wavy" surface brightness profile interior to $r$ $\\approx$ 110 AU, where the peaks/plateaus in the profiles are shifted between the NE and SW disk lobes. The SW side of the disk is 50--100% brighter at $r$ = 35-80 AU, and the location of its peak brightness roughly coincides with the disk's mm emission peak. Spectral energy distribution modeling suggests that HD 32297 has at least two dust populations that may originate from two separate belts likely at different locations, possibly at distances coinciding with the surface brightness peaks. A disk model for a single dust belt including a phase function with two components and a 5-10 AU pericenter offset explains the disk's warped structure and reproduces some of the surface br...
Directory of Open Access Journals (Sweden)
A.M. Yu
2012-01-01
Full Text Available Free vibration equations for non-cylindrical (conical, barrel, and hyperboloidal types helical springs with noncircular cross-sections, which consist of 14 first-order ordinary differential equations with variable coefficients, are theoretically derived using spatially curved beam theory. In the formulation, the warping effect upon natural frequencies and vibrating mode shapes is first studied in addition to including the rotary inertia, the shear and axial deformation influences. The natural frequencies of the springs are determined by the use of improved Riccati transfer matrix method. The element transfer matrix used in the solution is calculated using the Scaling and Squaring method and Pad'e approximations. Three examples are presented for three types of springs with different cross-sectional shapes under clamped-clamped boundary condition. The accuracy of the proposed method has been compared with the FEM results using three-dimensional solid elements (Solid 45 in ANSYS code. Numerical results reveal that the warping effect is more pronounced in the case of non-cylindrical helical springs than that of cylindrical helical springs, which should be taken into consideration in the free vibration analysis of such springs.
Gravitational backreaction of anti-D branes in the warped compactification
Koyama, K; Koyama, Kayoko; Koyama, Kazuya
2005-01-01
We derive a low-energy effective theory for gravity with anti-D branes, which are essential to get de Sitter solutions in the type IIB string warped compactification, by taking account of gravitational backreactions of anti-D branes. In order to see the effects of the self-gravity of anti-D branes, a simplified model is studied where a 5-dimensional anti-de Sitter ({\\it AdS}) spacetime is realized by the bulk cosmological constant and the 5-form flux, and anti-D branes are coupled to the 5-form field by Chern-Simon terms. The {\\it AdS} spacetime is truncated by introducing UV and IR cut-off branes like the Randall-Sundrum model. We derive an effective theory for gravity on the UV brane and reproduce the familiar result that the tensions of the anti-D branes give potentials suppressed by the forth-power of the warp factor at the location of the anti-D branes. However, in this simplified model, the potential energy never inflates the UV brane, although the anti-D-branes are inflating. The UV brane is dominated ...
Two-step flash light sintering of copper nanoparticle ink to remove substrate warping
Ryu, Chung-Hyeon; Joo, Sung-Jun; Kim, Hak-Sung
2016-10-01
A two-step flash light sintering process was devised to reduce the warping of polymer substrates during the sintering of copper nanoparticle ink. To determine the optimum sintering conditions of the copper nanoparticle ink, the flash light irradiation conditions (pulse power, pulse number, on-time, and off-time) were varied and optimized. In order to monitor the flash light sintering process, in situ resistance and temperature monitoring of copper nanoink were conducted during the flash light sintering process. Also, a transient heat transfer analysis was performed by using the finite-element program ABAQUS to predict the temperature changes of copper nanoink and polymer substrate. The microstructures of the sintered copper nanoink films were analyzed by scanning electron microscopy. Additionally, an X-ray diffraction and Fourier transform infrared spectroscopy were used to characterize the crystal phase change of the sintered copper nanoparticles. The resulting two-step flash light sintered copper nanoink films exhibited a low resistivity (3.81 μΩ cm, 2.3 times of that of bulk copper) and 5B level of adhesion strength without warping of the polymer substrate.
Astrophysical Implications of a Visible Dark Matter Sector from a Custodially Warped-GUT
Agashe, Kaustubh; Lee, Seung J; Perez, Gilad
2009-01-01
We explore, within the warped extra dimensional framework, the possibility of finding anti-matter signals in cosmic rays (CRs) from dark matter (DM) annihilation. Exchange of order 100 GeV radion, an integral part of our setup, generically results in Sommerfeld enhancement of the annihilation rate for TeV DM mass. No dark sector is required to obtain boosted annihilation cross sections. A mild hierarchy between the radion and DM masses can be natural due to the pseudo-Goldstone boson nature of the radion. Implications of Sommerfeld enhancement in warped grand unified theory (GUT) models, where proton stability implies a DM candidate, are studied. We show, via partially unified Pati-Salam group, how to incorporate a custodial symmetry for Z->b\\bar b into the GUT framework such that a few TeV Kaluza-Klein (KK) mass scale is allowed by precision tests. The model with smallest fully unified SO(10) representation allows us to decouple the DM from the electroweak sector. Thus, a correct DM relic density is obtained...
Illumination Tolerance for Visual Navigation with the Holistic Min-Warping Method
Directory of Open Access Journals (Sweden)
Ralf Möller
2014-02-01
Full Text Available Holistic visual navigation methods are an emerging alternative to the ubiquitous feature-based methods. Holistic methods match entire images pixel-wise instead of extracting and comparing local feature descriptors. In this paper we investigate which pixel-wise distance measures are most suitable for the holistic min-warping method with respect to illumination invariance. Two novel approaches are presented: tunable distance measures—weighted combinations of illumination-invariant and illumination-sensitive terms—and two novel forms of “sequential” correlation which are only invariant against intensity shifts but not against multiplicative changes. Navigation experiments on indoor image databases collected at the same locations but under different conditions of illumination demonstrate that tunable distance measures perform optimally by mixing their two portions instead of using the illumination-invariant term alone. Sequential correlation performs best among all tested methods, and as well but much faster in an approximated form. Mixing with an additional illumination-sensitive term is not necessary for sequential correlation. We show that min-warping with approximated sequential correlation can successfully be applied to visual navigation of cleaning robots.
银盘外区的翘曲结构%Warp of the Outer Region of the Galactic Disc
Institute of Scientific and Technical Information of China (English)
赵君亮
2011-01-01
It has been over 50 years since radio observations of neutral hydrogen first revealed the gaseous disk of the Milky Way Galaxy to be warped and flaring. Subsequently, such a structure has also been observed in the distribution of various components of the Galaxy in different wavebands, such as population I objects, molecular clouds, interstellar dust and older stellar population.Radio observations of neutral hydrogen were firstly used to find the warp and the flare of the outer gaseous disc of the Galaxy. The general warping of the H I layer above the Galactic plane in the north and below the plane in the south is clearly shown. According to the results obtained from some researches, for the north, the warping increases rapidly with galactocentric distance R, from the average distance above the plane z ~ 0.1 kpc at R ~ 13 kpc to z=4-4.5 kpc at R ~ 24-30 kpc, whereas in the south, it reaches an extreme value near R ~ 17 kpc and then returns to the plane z=0. At R > 24 kpc, the H I layer exhibits a "scalloping" up and down with respect to distances above the plane z= 0 as the azimuth is changed. The azimuth range of maximum warp directions is 90°- 110°. And the characteristic thickness, which can be used to describe the flaring outer disc, increases rapidly with increasing R, from 1 kpc at R ~ 14 kpc to 3.5-4 kpc at R ~ 24-30 kpc.The population I tracers, which can be used to detected the warp and flare structure of the outer stellar disc of the Galaxy, include OB stars, WR stars, classical cepheids, pulsars, open clusters and even supernova remnants, among which many studies have been done for OB stars since 1970. Prom some samples of such young stars, it has been found that the inclination of the plane denned by OB stars exterior to the solar circle is some 3° and the nodal line of the inclined plane with the Galactic plane is quite close to the Galactic center-Sun-anticenter line, which is in accordance with the global structure of the warped H I layer
Template-based automatic recognition of birdsong syllables from continuous recordings.
Anderson, S E; Dave, A S; Margoliash, D
1996-08-01
The application of dynamic time warping (DTW) to the automated analysis of continuous recordings of animal vocalizations is evaluated. The DTW algorithm compares an input signal with a set of predefined templates representative of categories chosen by the investigator. It directly compares signal spectrograms, and identifies constituents and constituent boundaries, thus permitting the identification of a broad range of signals and signal components. When applied to vocalizations of an indigo bunting (Passerina cyanea) and a zebra finch (Taeniopygia guttata) collected from a low-clutter, low-noise environment, the recognizer identifies syllables in stereotyped songs and calls with greater than 97% accuracy. Syllables of the more variable and lower amplitude indigo bunting plastic song are identified with approximately 84% accuracy. Under restricted recordings conditions, this technique apparently has general applicability to analysis of a variety of animal vocalizations and can dramatically decrease the amount of time spent on manual identification of vocalizations.
Toward fully self-consistent simulation of the interaction of E-Clouds and beams with WARP-POSINST
Energy Technology Data Exchange (ETDEWEB)
LLNL; Furman, M.A.; Furman, M.A.; Celata, C.M.; Sonnad, K.; Venturini, M.; Cohen, R.H.; Friedman, A.; Grote, D.P.; Vay, J.-L.
2012-04-09
To predict the evolution of electron clouds and their effect on the beam, the high energy physics community has relied so far on the complementary use of 'buildup' and 'single/multi-bunch instability' reduced descriptions. The former describes the evolution of electron clouds at a given location in the ring, or 'station', under the influence of prescribed beams and external fields [1], while the latter (sometimes also referred as the 'quasi-static' approximation [2]) follows the interaction between the beams and the electron clouds around the accelerator with prescribed initial distributions of electrons, assumed to be concentrated at a number of discrete 'stations' around the ring. Examples of single bunch instability codes include HEADTAIL [3], QuickPIC [4, 5], and PEHTS [6]. By contrast, a fully self-consistent approach, in which both the electron cloud and beam distributions evolve simultaneously under their mutual influence without any restriction on their relative motion, is required for modeling the interaction of high-intensity beams with electron clouds for heavy-ion beam-driven fusion and warm-dense matter science. This community has relied on the use of Particle-In-Cell (PIC) methods through the development and use of the WARP-POSINST code suite [1, 7, 8]. The development of novel numerical techniques (including adaptive mesh refinement, and a new 'drift-Lorentz' particle mover for tracking charged particles in magnetic fields using large time steps) has enabled the first application of WARP-POSINST to the fully self-consistent modeling of beams and electron clouds in high energy accelerators [9], albeit for only a few betatron oscillations. It was recently observed [10] that there exists a preferred frame of reference which minimizes the number of computer operations needed to simulate the interaction of relativistic objects. This opens the possibility of reducing the cost of fully self
Current Research and Development Trend of Warp-knitted Flexible Metal Mesh%经编柔性金属网研究现状及发展趋势
Institute of Scientific and Technical Information of China (English)
李楠; 蒋金华; 陈南梁
2015-01-01
With the rapid development of the satellite communication techniques, the warp-knitted flexible warp metal mesh has been used widely for large deployable antenna for space application. Based on this ,this paper stud-ies current research and developing trend of warp-knitted flexible metal mesh. Firstly , it introduces the concept. Secondly it describes the current research in terms of the design requirements, materials and knitting process. Thirdly, it tests the uniaxial tensile properties. Finally, some future directions are pointed out. Furthermore, it ana-lyzes the development trend of this kind mesh, which can provide some references for development of spatial de-ployable mesh antenna.%随着卫星通信技术的不断发展,经编柔性金属网在卫星天线上得到了广泛应用,基于此,对经编柔性金属网的研究现状及发展趋势展开研究. 介绍了经编柔性金属网的概念,从金属网的设计要求、编织材料和生产工艺等方面阐述了近年来经编柔性金属网的研究现状, 并对其单向拉伸性能进行了测试. 最后对经编柔性金属网的发展趋势进行了展望,为空间可展开网状天线的研究提供参考.
Stone, Wesley W.; Gilliom, Robert J.; Crawford, Charles G.
2008-01-01
Regression models were developed for predicting annual maximum and selected annual maximum moving-average concentrations of atrazine in streams using the Watershed Regressions for Pesticides (WARP) methodology developed by the National Water-Quality Assessment Program (NAWQA) of the U.S. Geological Survey (USGS). The current effort builds on the original WARP models, which were based on the annual mean and selected percentiles of the annual frequency distribution of atrazine concentrations. Estimates of annual maximum and annual maximum moving-average concentrations for selected durations are needed to characterize the levels of atrazine and other pesticides for comparison to specific water-quality benchmarks for evaluation of potential concerns regarding human health or aquatic life. Separate regression models were derived for the annual maximum and annual maximum 21-day, 60-day, and 90-day moving-average concentrations. Development of the regression models used the same explanatory variables, transformations, model development data, model validation data, and regression methods as those used in the original development of WARP. The models accounted for 72 to 75 percent of the variability in the concentration statistics among the 112 sampling sites used for model development. Predicted concentration statistics from the four models were within a factor of 10 of the observed concentration statistics for most of the model development and validation sites. Overall, performance of the models for the development and validation sites supports the application of the WARP models for predicting annual maximum and selected annual maximum moving-average atrazine concentration in streams and provides a framework to interpret the predictions in terms of uncertainty. For streams with inadequate direct measurements of atrazine concentrations, the WARP model predictions for the annual maximum and the annual maximum moving-average atrazine concentrations can be used to characterize
The use of cross-section warping functions in composite rotor blade analysis
Kosmatka, J. B.
1992-01-01
During the contracted period, our research was concentrated into three areas. The first was the development of an accurate and a computationally efficient method for predicting the cross-section warping functions in an arbitrary cross-section composed of isotropic and/or anisotropic materials. The second area of research was the development of a general higher-order one-dimensional theory for anisotropic beams. The third area of research was the development of an analytical model for assessing the extension-bend-twist coupling behavior of nonhomogeneous anisotropic beams with initial twist. In the remaining six chapters of this report, the three different research areas and associated sub-research areas are covered independently including separate introductions, theoretical developments, numerical results, and references.
Middleton, Chad A
2016-01-01
We present a theoretical and experimental analysis of the elliptical-like orbits of a marble rolling on a warped spandex fabric. We arrive at an expression describing the angular separation between successive apocenters, or equivalently successive pericenters, in both the small and large slope regimes. We find that a minimal angular separation of approximately 197 degrees is predicted for orbits with small radial distances when the surface is void of a central mass. We then show that for small radii and large central masses, when the orbiting marble is deep within the well, the angular separation between successive apocenters transitions to values greater than 360 degrees. We lastly compare these expressions to those describing elliptical-like orbits about a static, spherically symmetric massive object in the presence of a constant vacuum energy, as described by general relativity.
Yelgel, Celal
2016-04-01
We present an extensive density functional theory (DFT) based investigation of the electronic structures of ABC-stacked N-layer graphene. It is found that for such systems the dispersion relations of the highest valence and the lowest conduction bands near the K point in the Brillouin zone are characterised by a mixture of cubic, parabolic, and linear behaviours. When the number of graphene layers is increased to more than three, the separation between the valence and conduction bands decreases up until they touch each other. For five and six layer samples these bands show flat behaviour close to the K point. We note that all states in the vicinity of the Fermi energy are surface states originated from the top and/or bottom surface of all the systems considered. For the trilayer system, N = 3, pronounced trigonal warping of the bands slightly above the Fermi level is directly obtained from DFT calculations.
Canonical structure of BHT massive gravity in warped AdS{sub 3} sector
Energy Technology Data Exchange (ETDEWEB)
Mahdavian Yekta, Davood, E-mail: d.mahdavian@hsu.ac.ir
2016-08-10
We investigate the asymptotic structure of the three dimensional Warped Anti-de Sitter (WAdS{sub 3}) black holes in the Bergshoeff–Hohm–Townsend (BHT) massive gravity using the canonical Hamiltonian formalism. We define the canonical asymptotic gauge generators, which produce the conserved charges and the asymptotic symmetry group for the WAdS{sub 3} black holes. The attained symmetry group is described by a semi-direct sum of a Virasoro and a Kač–Moody algebra. Using the Sugawara construction, we obtain a direct sum of two Virasoro algebras. We show that not only the asymptotic conserved charges satisfy the first law of black hole thermodynamics, but also they lead to the expected Smarr formula for the WAdS{sub 3} black holes. We also show that the black hole's entropy obeys the Cardy formula of the dual conformal field theory (CFT).
Canonical structure of BHT massive gravity in warped AdS3 sector
Mahdavian Yekta, Davood
2016-08-01
We investigate the asymptotic structure of the three dimensional Warped Anti-de Sitter (WAdS3) black holes in the Bergshoeff-Hohm-Townsend (BHT) massive gravity using the canonical Hamiltonian formalism. We define the canonical asymptotic gauge generators, which produce the conserved charges and the asymptotic symmetry group for the WAdS3 black holes. The attained symmetry group is described by a semi-direct sum of a Virasoro and a Kač-Moody algebra. Using the Sugawara construction, we obtain a direct sum of two Virasoro algebras. We show that not only the asymptotic conserved charges satisfy the first law of black hole thermodynamics, but also they lead to the expected Smarr formula for the WAdS3 black holes. We also show that the black hole's entropy obeys the Cardy formula of the dual conformal field theory (CFT).
"Light" Higgs and warped models: Case for a Gigantic International Hadron Collider
Soni, Amarjit
2013-01-01
The LHC seems to have made a monumental discovery, Higgs-like particle of mass around 125 GeV with properties akin to a Standard Model Higgs. In the context of a warped theory of flavor, which is theoretically very attractive, this suggests Kaluza-Klein particle masses are likely to be above 10 TeV except possibly for a radion. The interpretation of the SM-like Higgs from the perspective of other interesting beyond the SM scenarios is also likely that the relevant scale is higher than accessible to the LHC. In light of these developments, deeper understanding of flavor and other fundamental issues requires a gigantic international hadron collider [GIHC] perhaps with cm energy of $\\approx$ 100 TeV \\cite{2talks}. It is suggested that a {\\it global effort} should be made for constructing this machine for resolving many questions that SM cannot answer.
Time travel and warp drives a scientific guide to shortcuts through time and space
Everett, Allen
2012-01-01
Sci-fi makes it look so easy. Receive a distress call from Alpha Centauri? No problem: punch the warp drive and you're there in minutes. Facing a catastrophe that can't be averted? Just pop back in the timestream and stop it before it starts. But for those of us not lucky enough to live in a science-fictional universe, are these ideas merely flights of fancy—or could it really be possible to travel through time or take shortcuts between stars?Cutting-edge physics may not be able to answer those questions yet, but it does offer up some tantalizing possibilities. In Time Travel and W
Observation of antiphase coherent phonons in the warped Dirac cone of Bi2Te3
Golias, E.; Sánchez-Barriga, J.
2016-10-01
In this Rapid Communication we investigate the coupling between excited electrons and phonons in the highly anisotropic electronic structure of the prototypical topological insulator Bi2Te3 . Using time- and angle-resolved photoemission spectroscopy we are able to identify the emergence and ultrafast temporal evolution of the longitudinal-optical A1 g coherent-phonon mode in Bi2Te3 . We observe an antiphase behavior in the onset of the coherent-phonon oscillations between the Γ K ¯ and the Γ M ¯ high-symmetry directions that is consistent with warping. The qualitative agreement between our density-functional theory calculations and the experimental results reveals the critical role of the anisotropic coupling between Dirac fermions and phonon modes in the topological insulator Bi2Te3 .
Influence of Manufacturing Process of Warp-knitted Vascular Prosthesis on the Wall Homogeneity
Institute of Scientific and Technical Information of China (English)
王璐; 丁辛
2003-01-01
This paper reports the evolution of textile structure and mechanical properties of vascular prosthesis in the level of the whole prosthesis and the constituent filaments with respect to the manufacturing process.The tubular wall of the prosthesis is divided circumferentially into three zones: basic line (BL),remeshing line (RL) and guide line (GL). Some heterogeneity has been observed on the tubular wall in :erms of stitch structure of the prosthesis and linear density of the constituent filaments. The breaking position of the prosthesis under circumferential tensile localizes preferentially in remeshing line that is the weakest zone by warp knitting with double needle bed. Furthermore, the statistical differences of the mechanical properties of the filaments of zone RL, GL and BL have been confirmed too. It is predictable that the deterioration of prosthesis, under physiological loads (periodical pulse blood pressure etc.), could happen firstly in the weaker zone in vivo.
Higgs-gluon coupling in warped extra dimensional models with brane kinetic terms
Dey, Ujjal Kumar; Ray, Tirtha Sankar
2016-01-01
Warped models with the Higgs confined to the weak brane and the gauge and matter fields accessing the AdS5 bulk provide a viable setting to address the gauge hierarchy problem. Brane kinetic terms for the bulk fields are known to ease some of the tensions of these models with precision electroweak observables and flavor constraints. We study the loop-driven Higgs coupling to the gluons that are relevant to the Higgs program at the LHC, in this scenario. We demonstrate a partial cancellation in the contribution of the fermionic Kaluza-Klein (KK) towers within such framework relatively independent of the 5D parameters. The entire dependence of this coupling on the new physics arises from the mixing between the Standard Model states and the KK excitations. We find that the present precision in measurement of these couplings can lead to a constraint on the KK scale up to 1.2 TeV at 95% confidence level.
Flavor-changing decays of the top quark in 5D warped models
Díaz-Furlong, Alfonso; Frank, Mariana; Pourtolami, Nima; Toharia, Manuel; Xoxocotzi, Reyna
2016-08-01
We study flavor-changing neutral current decays of the top quark in the context of general warped extra dimensions, where the five-dimensional (5D) metric is slightly modified from 5D anti-de Sitter (AdS5 ). These models address the Planck-electroweak hierarchies of the Standard Model and can obey all the low-energy flavor bounds and electroweak precision tests, while allowing the scale of new physics to be at the TeV level, and thus within the reach of the LHC at Run II. We perform the calculation of these exotic top decay rates for the case of a bulk Higgs, and thus include in particular the effect of the additional Kaluza-Klein (KK) Higgs modes running in the loops, along with the usual KK fermions and KK gluons.
Evaluating consistency of deterministic streamline tractography in non-linearly warped DTI data
Adluru, Nagesh; Tromp, Do P M; Davidson, Richard J; Zhang, Hui; Alexander, Andrew L
2016-01-01
Tractography is typically performed for each subject using the diffusion tensor imaging (DTI) data in its native subject space rather than in some space common to the entire study cohort. Despite performing tractography on a population average in a normalized space, the latter is considered less favorably at the \\emph{individual} subject level because it requires spatial transformations of DTI data that involve non-linear warping and reorientation of the tensors. Although the commonly used reorientation strategies such as finite strain and preservation of principle direction are expected to result in adequate accuracy for voxel based analyses of DTI measures such as fractional anisotropy (FA), mean diffusivity (MD), the reorientations are not always exact except in the case of rigid transformations. Small imperfections in reorientation at individual voxel level accumulate and could potentially affect the tractography results adversely. This study aims to evaluate and compare deterministic white matter fiber t...
Effect of Carboxymethyl Starch as Stabilizer for Increasing the Stability of Warp Sizing Pastes
Institute of Scientific and Technical Information of China (English)
祝志峰; 梁茵
2003-01-01
The influences of carboxymethyl starch used as stabilizer upon the stability of native cornstarchpolyvinyl alcohol blend pastes for warp sizing have been investigated. The effect of the modified starch on the paste stability was evaluated in terms of the initial demixing time and the volume percentage of separated starch. The carboxymethyl starch with a series of different degrees of substitution was prepared in ethanol dispersion by varying the amount of monochloroacetic acid reacted with refined native cornstarch. The paste stability strongly depends on the modification extent and amount of carboxymethyl starch used, and on native starch content in the paste. Increase in the modification extent and/or the amount of the modified starch effectively retards the phase separation and reduces the separation extent of native cornstarch-polyvinyl alcohol blend pastes.Moreover, the mechanism and favorable modification extent of carboxymethyl starch for enhancing paste stability are also investigated and discussed.
Virial mass in warped DGP-inspired L(R) gravity
Heydari-Fard, Malihe
2012-01-01
A version of the virial theorem is derived in a brane-world scenario in the framework of a warped DGP model where the action on the brane is an arbitrary function of the Ricci scalar, L(R). The extra terms in the modified Einstein equations generate an equivalent mass term (geometrical mass), which give an effective contribution to the gravitational energy and offer viable explanation to account for the virial mass discrepancy in clusters of galaxies. We also obtain the radial velocity dispersion of galaxy clusters and show that it is compatible with the radial velocity dispersion profile of such clusters. Finally, we compare the result of the model with L(R) gravity theories.
Canonical structure of BHT massive gravity in warped AdS3 sector
Directory of Open Access Journals (Sweden)
Davood Mahdavian Yekta
2016-08-01
Full Text Available We investigate the asymptotic structure of the three dimensional Warped Anti-de Sitter (WAdS3 black holes in the Bergshoeff–Hohm–Townsend (BHT massive gravity using the canonical Hamiltonian formalism. We define the canonical asymptotic gauge generators, which produce the conserved charges and the asymptotic symmetry group for the WAdS3 black holes. The attained symmetry group is described by a semi-direct sum of a Virasoro and a Kač–Moody algebra. Using the Sugawara construction, we obtain a direct sum of two Virasoro algebras. We show that not only the asymptotic conserved charges satisfy the first law of black hole thermodynamics, but also they lead to the expected Smarr formula for the WAdS3 black holes. We also show that the black hole's entropy obeys the Cardy formula of the dual conformal field theory (CFT.
The Dimensional Reduction and K\\"ahler Metric of Forms In Flux and Warping
Frey, Andrew R
2013-01-01
We present a first-principles derivation of the K\\"ahler metric for axion-like moduli of conformally Calabi-Yau compactifications of IIB string theory with imaginary self-dual 3-form flux at the classical level. We find that the warp factor and flux modify the moduli space metric and therefore K\\"ahler potential even in classical supergravity, with the modifications scaling as (volume)$^{-2/3}$ in the large-volume limit. Our derivation emphasizes the role of constraints from 10D gauge symmetries and highlights metric formality as a geometric property that protects the moduli space of highly supersymmetric toroidal orientifolds. Our results have important quantitative implications for nonperturbative moduli stabilization, phenomenology, and cosmology in flux compactifications.
Manifestations of Warped Extra Dimension in Rare Charm Decays and Asymmetries
Paul, Ayan; Bigi, Ikaros I
2012-01-01
Charm dynamics is moving back into focus with the established discovery of oscillations in the neutral D meson system and the sign of direct CP asymmetry in D0 to pi+ pi- / K+ K-. It opens the possibilities of finding CP violation beyond the reach of the Standard Model. In the recent past we have extensively studied charm dynamics within non-ad-hoc models with interesting flavour structures. We have shown that rare decays and CP violations are the best places to probe for New Dynamics in charm. We continue to study a different class of models, i.e., the Randall Sundrum model with a warped extras dimension to check for unusual effects in charm dynamics: namely in decays of final states with leptons and neutrinos and some asymmetries. These states should typically be accessible to experimental probes in the near future and, for certain, to any super flavour factory.
Thermal comfort of diving dry suit with the use of the warp-knitted fabric
Lenfeldova, I.; Hes, L.; Annayeva, M.
2016-07-01
Achievement of a good level of thermal comfort of under-suits for dry suit diving which enable also the required mobility of the diver in water is inevitable not only for the scuba sport and commercial diving people but also for safety and activities of people who make research under water. The aim of this work is to verify whether selected knitted structures (which are not waterproof) can substitute the currently used textile materials (nonwovens). This dry-suit innovation is intended to increase the properties which correspond to the perception of thermal comfort of the diver in water. To achieve this objective, the Alambeta thermal tester was used in the study for experimental determination of thermal resistance of spacer warp knitted fabric at varying contact pressure. The studied textiles were expected to be very suitable for the intended application due to their low compressibility which yields relatively high thickness a hence increased thermal insulation.
Realistic D-Brane Models on Warped Throats: Fluxes, Hierarchies and Moduli Stabilization
Cascales, J F G; Quevedo, Fernando; Uranga, Angel M
2004-01-01
We describe the construction of string theory models with semirealistic spectrum in a sector of (anti) D3-branes located at an orbifold singularity at the bottom of a highly warped throat geometry, which is a generalisation of the Klebanov-Strassler deformed conifold. These models realise the Randall-Sundrum proposal to naturally generate the Planck/electroweak hierarchy in a concrete string theory embedding, and yielding interesting chiral open string spectra. We describe examples with Standard Model gauge group (or left-right symmetric extensions) and three families of SM fermions, with correct quantum numbers including hypercharge. The dilaton and complex structure moduli of the geometry are stabilised by the 3-form fluxes required to build the throat. We describe diverse issues concerning the stabilisation of geometric Kahler moduli, like blow-up modes of the orbifold singularities, via D term potentials and gauge theory non-perturbative effects, like gaugino condensation. This local geometry, once embedd...
Disordered Speech Assessment Using Automatic Methods Based on Quantitative Measures
Directory of Open Access Journals (Sweden)
Christine Sapienza
2005-06-01
Full Text Available Speech quality assessment methods are necessary for evaluating and documenting treatment outcomes of patients suffering from degraded speech due to Parkinson's disease, stroke, or other disease processes. Subjective methods of speech quality assessment are more accurate and more robust than objective methods but are time-consuming and costly. We propose a novel objective measure of speech quality assessment that builds on traditional speech processing techniques such as dynamic time warping (DTW and the Itakura-Saito (IS distortion measure. Initial results show that our objective measure correlates well with the more expensive subjective methods.
A planet on an inclined orbit as an explanation of the warp in the $\\beta$ Pictoris disk
Mouillet, D; Papaloizou, J C B; Lagrange, A M
1997-01-01
We consider the deformation that has recently been observed in the inner part of the circumstellar disk around Beta Pictoris with the HST. Our recent ground based adaptive optics coronographic observations confirm that the inner disk is warped. We investigate the hypothesis that a yet undetected planet is responsible for the observed warp, through simulations of the effect of the gravitational perturbation due to a massive companion on the disk. The physical processes assumed in the simulations are discussed: since the observed particles do not survive collisions, the apparent disk shape is driven by the underlying collisionless parent population. The resulting possible parameters for the planet that are consistent with the observed disk deformation are reviewed.
2016-01-01
Probing the warped side of our Universe with gravitational waves and computer simulations, by Kip Thorne, recipient of the Tomalla Prize for Gravity 2016. "Probing the warped side of our Universe with gravitational waves and computer simulations" Uni Dufour - Auditorium U300 Friday, 16 September at 6 p.m. Kip Thorne. (Photo: ©Jon Rou) Abstract: A half century ago, John Wheeler challenged his students and colleagues to explore Geometrodynamics: the nonlinear dynamics of curved spacetime. How does the curvature of spacetime behave when roiled in a storm, like a storm at sea with crashing waves. We tried to explore this, and failed. Success eluded us until two new tools became available: computer simulations, and gravitational wave observations. Thorne will describe what these have begun to teach us, and he will offer a vision for the future of Geometrodynamics.
经编无缝船袜的开发%Development of Warp Knitted Seamless Boat Socks
Institute of Scientific and Technical Information of China (English)
姚馨馨; 丛洪莲
2015-01-01
经编无缝船袜是由双针床拉舍尔经编机生产的一次成型织物。船袜又称“隐形袜”，鞋子可将袜面部分罩住。经编无缝船袜款式多样，花型丰富，且无缝合，吸湿排汗，穿着十分舒适。本课题介绍了船袜的生产设备、多款经编无缝船袜的不同特点，选用花型时的注意点以及船袜的功能性特点，如利用硅胶使得经编无缝船袜摒弃易滑脱的缺陷等。简单介绍船袜的开发过程。未来经编无缝船袜需要从新原料、新款式、新工艺等角度出发，获得更广阔的市场。%Warp knitted seamless boat socks were produced by a double bar raschel machine. It is called in-visible boat socks whose face can be covered by shoes. Warp knitted seamless boat socks have diverse styles and rich patterns, they are moisture absorbable, breathable and comfortable. Some main points of boat socks were in-troduced such as the production equipment, different characteristics with diverse styles, key points for selecting patterns and its functional features such as the use of silica gel which made the warp knitted seamless boat socks hard to slip. The development process of boat socks was briefly introduced. From the perspective of new materi-als, new style and new technology, the future of warp knitted seamless socks will have a broader market.
A WARP IN PROGRESS: H I AND RADIO CONTINUUM OBSERVATIONS OF THE SPIRAL NGC 3145
Energy Technology Data Exchange (ETDEWEB)
Kaufman, Michele [110 Westchester Rd, Newton, MA 02458 (United States); Brinks, Elias [University of Hertfordshire, Centre for Astrophysics Research, College Lane, Hatfield AL10 9AB (United Kingdom); Struck, Curtis [Department of Physics and Astronomy, Iowa State University, Ames, IA 50011 (United States); Elmegreen, Bruce G. [IBM Research Division, T.J. Watson Research Center, 1101 Kitchawan Rd., Yorktown Heights, NY 10598 (United States); Elmegreen, Debra M., E-mail: kaufmanrallis@icloud.com, E-mail: E.Brinks@herts.ac.uk, E-mail: curt@iastate.edu, E-mail: bge@us.ibm.com, E-mail: elmegreen@vassar.edu [Department of Physics and Astronomy, Vassar College, 124 Raymond Av., Poughkeepsie, NY 12604 (United States)
2015-09-15
VLA H i observations and λ6 cm radio continuum observations are presented of the barred-spiral galaxy NGC 3145. In optical images NGC 3145 has stellar arms that appear to cross, forming “X”-features. Our radio continuum observations rule out shock fronts at three of the four “X”-features, and our H i data provide evidence of gas motions perpendicular to the disk of NGC 3145. In large portions of NGC 3145, particularly in the middle-to-outer disk, the H i line profiles are skewed. Relative to the disk, the gas in the skewed wing of the line profiles has z-motions away from us on the approaching side of the galaxy and z-motions of about the same magnitude (∼40 km s{sup −1}) toward us on the receding side. These warping motions imply that there has been a perturbation with a sizeable component perpendicular to the disk over large spatial scales. Two features in NGC 3145 have velocities indicating that they are out-of-plane tidal arms. One is an apparent branch of a main spiral arm on the northeastern side of NGC 3145; the velocity of the branch is ∼150 km s{sup −1} greater than the spiral arm where they appear to intersect in projection. The other is the arm on the southwestern side that forms three of the “X”-features. It differs in velocity by ∼56 km s{sup −1} from that of the disk at the same projected location. H i observations are presented also of the two small companions NGC 3143 and PGC 029578. Based on its properties (enhanced SFR, H i emission 50% more extended on its northeastern side, etc.), NGC 3143 is the more likely of the two companions to have interacted with NGC 3145 recently. A simple analytic model demonstrates that an encounter between NGC 3143 and NGC 3145 is a plausible explanation for the observed warping motions in NGC 3145.
Numerical study on the curling and warping of hardened rigid pavement slabs
Qin, Yinghong
In-service hardened concrete pavement suffers from environmental loadings caused by curling and warping of the slab. Traditionally, these loadings are computed on the basis of treating the slab as an elastic material, and of evaluating separately the curling and warping components. This dissertation simulates temperature distribution and moisture distribution through the slabs by use of a developed numerical model that couples the heat transfer and moisture transport. The computation of environmental loadings treats the slab as an elastic-viscous material, which considers the relaxation behavior and Pickett effect of the concrete. The heat transfer model considers the impacts of solar radiation, wind speed, air temperature, pavement slab albedo, etc. on the pavement temperature distribution. This dissertation assesses the difference between documented models that aim to predict pavement temperature, highlighting their pros and cons. The moisture transport model is unique for the documented models; it mimics the wetting and drying events occurring at the slab surface. These events are estimated by a proposed statistical algorithm, which is verified by field rainfall data. Analysis of the predicted results examines on the roles of the local air RH (relative humidity), wind speed, rainy pattern in the moisture distribution through the slab. The findings reveal that seasonal air RH plays a decisive role on the slab's moisture distribution; but wind speed and its daily variation, daily RH variation, and seasonal rainfall pattern plays only a secondary role. This dissertation sheds light on the computation of environmental loadings that in-service pavement slabs suffer from. Analysis of the computed stresses centers on the stress relaxation near the surface, stress evolution after the curing ends, and the impact of construction season on the stress's magnitude. An unexpected finding is that the total environmental loadings at the cyclically-stable state divert from the
On the possibility of a warped disc origin of the inclined stellar discs at the Galactic Centre
Ulubay-Siddiki, A; Gerhard, O
2012-01-01
(Abridged) The Galactic Center (GC) hosts a population of young stars some of which seem to form mutually inclined discs of clockwise and counter clockwise rotating stars. We present a warped disc origin scenario for these stars assuming that an initially flat accretion disc becomes warped due to the Pringle instability, or due to Bardeen-Petterson effect, before it fragments to stars. We show that this is plausible if the star formation efficiency $\\epsilon_{SF} \\lesssim 1$, and the viscosity parameter $\\alpha \\sim 0.1$. After fragmentation, we model the disc as a collection of concentric, circular, mutually tilted rings, and construct warped disc models for mass ratios and other parameters relevant to the GC environment, but also for more massive discs. We take into account the disc's self-gravity and the torques exerted by a surrounding star cluster. We show that a self-gravitating low-mass disc ($M_d / M_{bh} \\sim 0.001$) precesses in integrity in the life-time of the stars, but precesses freely when the ...
Övgün, A.; Jusufi, Kimet
2017-07-01
This paper discusses the effects of the mass and angular momentum of massive vector and scalar particles on the Hawking temperature manifested under the effects of the generalized uncertainty principle (GUP). In particular, we calculate the Hawking temperature of a black hole in a warped DGP gravity model in the framework of the quantum tunneling method. We use the modified Proca and Klein-Gordon equations previously determined from the GUP Lagrangian in the spacetime background of a warped Dvali-Gabadadze-Porrati (DGP) metric, with the help of Hamilton-Jacobi (HJ) and semiclassical (WKB) approximation methods. We find that as a special case of a warped DGP black hole solution, the Hawking temperature of a Schwarzschild-de Sitter (SdS) black hole can be determined. Furthermore, the Hawking temperature is influenced by the mass and the angular momentum of vector and scalar particles and depends on which of those types of particles is being emitted by the black hole. We conclude that the nonthermal nature of the Hawking spectrum leads to Planck-scale nonthermal correlations, shedding light on the information paradox in black hole evaporation.
Precession of Magnetically Driven Warped Disks and Low-Frequency QPOs in Low-Mass X-Ray Binaries
Shirakawa, A; Shirakawa, Akiko; Lai, Dong
2000-01-01
An accretion disk around a rotating magnetized star is subjected to magnetic torques which induce disk warping and precession. These torques arise generically from interactions between the stellar field and the induced surface currents on the disk. Applying these new effects to weakly magnetized ($B\\sim$ $10^7$-$10^9$ G) neutron stars in low-mass X-ray binaries, we study the global hydrodynamical warping/precession modes of the disk under the combined influences of relativistic frame dragging and the magnetic torques. Under quite general conditions, the magnetic warping torque can overcome the ``Bardeen-Petterson'' viscous damping and makes the modes grow. The modes are confined to the inner region of the disk, and have frequencies close to the sum of the Lense-Thirring frequency and the magnetically driven precession frequency evaluated at the inner disk radius. Since the magnetically driven precession is retrograde (and opposite to the Lense-Thrring precession), the mode frequency can have a non-monotonic d...
Energy Technology Data Exchange (ETDEWEB)
Labaria, George R. [Univ. of California, Santa Cruz, CA (United States); Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Warrick, Abbie L. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Celliers, Peter M. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Kalantar, Daniel H. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
2015-01-12
The National Ignition Facility (NIF) at the Lawrence Livermore National Laboratory is a 192-beam pulsed laser system for high-energy-density physics experiments. Sophisticated diagnostics have been designed around key performance metrics to achieve ignition. The Velocity Interferometer System for Any Reflector (VISAR) is the primary diagnostic for measuring the timing of shocks induced into an ignition capsule. The VISAR system utilizes three streak cameras; these streak cameras are inherently nonlinear and require warp corrections to remove these nonlinear effects. A detailed calibration procedure has been developed with National Security Technologies (NSTec) and applied to the camera correction analysis in production. However, the camera nonlinearities drift over time, affecting the performance of this method. An in-situ fiber array is used to inject a comb of pulses to generate a calibration correction in order to meet the timing accuracy requirements of VISAR. We develop a robust algorithm for the analysis of the comb calibration images to generate the warp correction that is then applied to the data images. Our algorithm utilizes the method of thin-plate splines (TPS) to model the complex nonlinear distortions in the streak camera data. In this paper, we focus on the theory and implementation of the TPS warp-correction algorithm for the use in a production environment.
A New Fate of a Warped 5D FRW Model with a U(1) Scalar Gauge Field
Slagter, Reinoud Jan
2015-01-01
If we live on the weak brane with zero effective cosmological constant in a warped 5D bulk spacetime , gravitational waves and brane fluctuations can be generated by a part of the 5D Weyl tensor and carries information of the gravitational field outside the brane. We consider on a cylindrical symmetric warped FRW background the U(1) self-gravitating scalar-gauge field without bulk matter. It turns out that "branons" can be formed dynamically, due to the modified energy-momentum tensor components of the cosmic string. As a result, we find that the late-time behavior could be significant deviate from the standard evolution of the universe. The effect is triggered by the time-dependent warp factor, of the form $\\sqrt{ae^{\\tau t}+be^{-\\tau t}}$ and the modified brane equations, comparable with a dark energy effect. This is a brane-world mechanism, not present is standard 4D FRW, where the large disturbances are rapidly damped as the expansion proceed. Because gravity can propagate in the bulk, the cosmic string c...
Combined Dynamic Time Warping with Multiple Sensors for 3D Gesture Recognition.
Choi, Hyo-Rim; Kim, TaeYong
2017-08-17
Cyber-physical systems, which closely integrate physical systems and humans, can be applied to a wider range of applications through user movement analysis. In three-dimensional (3D) gesture recognition, multiple sensors are required to recognize various natural gestures. Several studies have been undertaken in the field of gesture recognition; however, gesture recognition was conducted based on data captured from various independent sensors, which rendered the capture and combination of real-time data complicated. In this study, a 3D gesture recognition method using combined information obtained from multiple sensors is proposed. The proposed method can robustly perform gesture recognition regardless of a user's location and movement directions by providing viewpoint-weighted values and/or motion-weighted values. In the proposed method, the viewpoint-weighted dynamic time warping with multiple sensors has enhanced performance by preventing joint measurement errors and noise due to sensor measurement tolerance, which has resulted in the enhancement of recognition performance by comparing multiple joint sequences effectively.
Supersymmetry of IIA warped flux AdS and flat backgrounds
Beck, S.; Gutowski, J.; Papadopoulos, G.
2015-09-01
We identify the fractions of supersymmetry preserved by the most general warped flux AdS and flat backgrounds in both massive and standard IIA supergravities. We find that AdS n × w M 10 - n preserve {2}^{[n/2]}k for n ≤ 4 and {2}^{[n/2]+1}k for 4 0. In addition we show that, for suitably restricted fields and M 10 - n , the killing spinors of AdS backgrounds are given in terms of the zero modes of Dirac like operators on M 10 - n . This generalizes the Lichnerowicz theorem for connections whose holonomy is included in a general linear group. We also adapt our results to ℝ 1, n - 1 × w M 10 - n backgrounds which underpin flux compactifications to ℝ 1, n - 1 and show that these preserve {2}^{[n/2]}k for 2
A Warp in Progress: H I and Radio Continuum Observations of the Spiral NGC 3145
Kaufman, Michele; Struck, Curtis; Elmegreen, Bruce G; Elmegreen, Debra M
2015-01-01
We present VLA H I and 6 cm radio continuum observations of the spiral NGC 3145 and H I observations of its two companions, NGC 3143 and PGC 029578. In optical images NGC 3145 has stellar arms that appear to cross, forming "X"-features. Our radio continuum observations rule out shock fronts at 3 of the 4 "X"-features. In the middle-to-outer disk, the H I line-profiles of NGC 3145 are skewed. Relative to the disk, the gas in the skewed wing of the line-profiles has z-motions away from us on the approaching side of the galaxy and z-motions of about the same magnitude (about 40 km/s) towards us on the receding side. These warping motions imply that there has been a perturbation perpendicular to the disk over large spatial scales. Two features in NGC 3145 have velocities indicating that they are out-of-plane tidal arms. One is an apparent branch of a main spiral arm; the velocity of the branch is 150 km/s greater than the spiral arm where they appear to intersect in projection. The other is an arm that forms 3 of...
Space Warps: I. Crowd-sourcing the Discovery of Gravitational Lenses
Marshall, Phil; More, Anupreeta; Davis, Chris; More, Surhud; Kapadia, Amit; Parrish, Michael; Snyder, Chris; Wilcox, Julianne; Baeten, Elisabeth; Macmillan, Christine; Cornen, Claude; Baumer, Michael; Simpson, Edwin; Lintott, Chris; Miller, David; Paget, Edward; Simpson, Robert; Smith, Arfon; Kueng, Rafael; Saha, Prasenjit; Collett, Tom; Tecza, Matthias
2015-01-01
We describe Space Warps, a novel gravitational lens discovery service that yields samples of high purity and completeness through crowd-sourced visual inspection. Carefully produced colour composite images are displayed to volunteers via a classi- fication interface which records their estimates of the positions of candidate lensed features. Simulated lenses, and expert-classified images which lack lenses, are inserted into the image stream at random intervals; this training set is used to give the vol- unteers feedback on their performance, as well as to calibrate it in order to allow dynamical updates to the probability of any image they classify to contain a lens. Low probability systems are retired from the site periodically, concentrating the sample towards a set of candidates. Having divided 160 square degrees of Canada-France- Hawaii Telescope Legacy Survey (CFHTLS) imaging into some 430,000 overlapping 84 by 84 arcsecond tiles and displaying them on the site, we were joined by around 37,000 volunteers...
Combining point context and dynamic time warping for online gesture recognition
Mao, Xia; Li, Chen
2017-05-01
Previous gesture recognition methods usually focused on recognizing gestures after the entire gesture sequences were obtained. However, in many practical applications, a system has to identify gestures before they end to give instant feedback. We present an online gesture recognition approach that can realize early recognition of unfinished gestures with low latency. First, a curvature buffer-based point context (CBPC) descriptor is proposed to extract the shape feature of a gesture trajectory. The CBPC descriptor is a complete descriptor with a simple computation, and thus has its superiority in online scenarios. Then, we introduce an online windowed dynamic time warping algorithm to realize online matching between the ongoing gesture and the template gestures. In the algorithm, computational complexity is effectively decreased by adding a sliding window to the accumulative distance matrix. Lastly, the experiments are conducted on the Australian sign language data set and the Kinect hand gesture (KHG) data set. Results show that the proposed method outperforms other state-of-the-art methods especially when gesture information is incomplete.
The Woof and the Warp of Architecture: The Figure-Ground in Urban Design
Directory of Open Access Journals (Sweden)
B.D. Wortham-Galvin
2014-08-01
Full Text Available To borrow a metaphor used by Georg W.F. Hegel in the Philosophy of History to describe historical processes, architecture should be understood as a series of complex threads wherein one recognizes the physical forms as the warp, and the temporal, socio-political, natural, and aural contexts as the woof. Fabric is asserted as a concept broader than the immediate spatial and physical situation in which individual buildings are located; and, the threads of the fabric are all of those elements that aid in making the built environment both a designed and lived experience.In order to discuss this proposed understanding of fabric, this paper will look at how drawings informed the process and theory of urban design in the mid- to late-twentieth century. The discussion will focus on the origins of the Nolli plan and its 'rediscovery' by the Cornell School and their use of the figure-ground as a primary tool in the formulation of an urban design theory. The trajectory of the figure-ground can reinvigorate contemporary urban design praxis once more by reasserting drawing as more than mere illustration but as a means to conceptualize design methodologies that support a holistic notion of fabric.
PRACTICAL CONTRIBUTIONS TO THE STUDY OF RESISTANCE ASSEMBLIES MADE WITH WARP KNITS
Directory of Open Access Journals (Sweden)
OANA Ioan-Pavel
2014-05-01
Full Text Available Based on the principle that a body to be obtained by sewing the material to provide resistance and the like in the stitching assembly, the experimental study of which developed resistance is compared with the resistance materials to effectively assembled by the assembly line. The experimental values resistance for assemblies were obtained in the testing for resistance to sliding stitch ASTM D 434 using Tinius Olsen HK5T test type machine. The assembly strength was determined for warp knitted fabric and satin charmeuse, made of poly-filamentary wires and mono-filament polyester and polyamide. Resistance assembling is one of the major determinants of the quality of the stitching. It is defined as "the tensile strength or friction." Tenacity stitching seam rupture is the force recorded at its weakest point. Seam abrasion resistance is the number of cycles required friction mesh destruction of seam. It can be said that the strength of the used assembly, the seam 301 is achieved by, in most of the cases, lower resistance knitted studied. In these cases, the primary findings presented, it is clear that the assembly is not appropriate in terms of reliability and maintainability of the product. Such a situation requires a first step to change the type (class of stitch used. Another way to remedy the deficiencies could be using a sewing thread with a lower finesse or strength in grain, especially in the upper loop of wire used in the study-specific.
Dermitzakis, Konstantinos; Arieta, Alejandro Hernandez; Pfeifer, Rolf
2011-01-01
One of the significant challenges in the upper-limb-prosthetics research field is to identify appropriate interfaces that utilize the full potential of current state-of-the-art neuroprostheses. As the new generation of such prostheses paces towards approximating the human physiological performance in terms of movement dexterity and sensory feedback, it is clear that current non-invasive interfaces are still severely limited. Surface electromyography, the interface ubiquitously used in the field, is riddled with several shortcomings. Gesture recognition, an interface pervasively used in wearables and mobile devices, shows a strong potential as a non-invasive upper-limb prosthetic interface. This study aims at showcasing its potential in the field by using gyroscope sensors. To this end, we (1) explore the viability of Dynamic Time Warping as a classification method for upper-limb prosthetics and (2) look for appropriate sensor locations on the body. Results indicate an optimal classification rate of 97.53%, σ = 8.74 using a sensor located proximal to the endpoint performing a gesture.
Warped $AdS_6\\times S^2$ in Type IIB supergravity I: Local solutions
D'Hoker, Eric; Karch, Andreas; Uhlemann, Christoph F
2016-01-01
We investigate the existence of solutions with 16 residual supersymmetries to Type IIB supergravity on a space-time of the form $AdS_6 \\times S^2$ warped over a two-dimensional Riemann surface $\\Sigma$. The $SO(2,5) \\times SO(3)$ isometry extends to invariance under the exceptional Lie superalgebra $F(4)$. In the present paper, we construct the general Ansatz compatible with these symmetries, derive the corresponding reduced BPS equations, and obtain their complete local solution in terms of two locally holomorphic functions ${\\cal A}_\\pm$ on $\\Sigma$, subject to certain positivity and regularity conditions. Globally, $({\\cal A}_+, {\\cal A}_-)$ are allowed to be multiple-valued on $\\Sigma$ and be holomorphic sections of a holomorphic bundle over $\\Sigma$ with structure group contained in $SU(1,1) \\times { C}$. Globally regular solutions are expected to provide the near-horizon geometry of $(p,q)$ 5-brane and 7-brane webs which are holographic duals to five-dimensional conformal field theories. A preliminary a...
Superconformal symmetry in the Kaluza-Klein spectrum of warped AdS(3)
Energy Technology Data Exchange (ETDEWEB)
Schmude, Johannes; Vasilakis, Orestis [Department of Physics, Universidad de Oviedo, Avda. Calvo Sotelo 18, 33007, Oviedo (Spain)
2016-10-18
We study the Kaluza-Klein spectrum of warped AdS{sub 3} compactifications of type IIB with five-form flux which are dual to N=(0,2) SCFTs in two dimensions. We prove that the spectra of fluctuations of both the spin 2 sector of the graviton and the axio-dilaton are bounded. At the bound the modes have the correct quantum numbers to be chiral primaries and descendants thereof respectively. Moreover, we prove that the same modes give rise to superpartners in the dilatino spectrum. Our results show that a subset of the mesonic chiral ring of the dual SCFT is isomorphic to the first Kohn-Rossi cohomology groups. As an example, we consider the compactification of four-dimensional Y{sup p,q} theories on Riemann surfaces for the case of the universal twist. We conclude by studying fluctuations of the three-form, where we are able to identify Betti multiplets after imposing some mild assumptions.
Gravitons in multiply warped scenarios: At 750GeV and beyond
Indian Academy of Sciences (India)
MATHEW THOMAS ARUN; PRATISHRUTI SAHA
2017-06-01
The search for extra dimensions has so far yielded no positive results at the LHC. Along with the discovery of a 125 GeV Higgs boson, this implies a moderate degree of fine-tuning in the parameter space of the Randall–Sundrum model. Within a six-dimensional warped compactification scenario, with its own interesting phenomenological consequences, the parameters associated with the additional spatial direction can be used to eliminate the need for fine-tuning.We examine the constraints on this model due to the 8 TeV LHC data and survey the parameter space that can be probed at the 14 TeV run of the LHC. We also identify the region of parameter space that is consistent with the recently reported excess in the diphoton channel in the 13 TeV data. Finally, as an alternative explanation for the observed excess, we discuss a scenario with brane-localized Einstein–Hilbert terms with Standard Model fields in the bulk.
Warps and waves in the stellar discs of the Auriga cosmological simulations
Gómez, Facundo A.; White, Simon D. M.; Grand, Robert J. J.; Marinacci, Federico; Springel, Volker; Pakmor, Rüdiger
2017-03-01
Recent studies have revealed an oscillating asymmetry in the vertical structure of the Milky Way's disc. Here, we analyse 16 high-resolution, fully cosmological simulations of the evolution of individual Milky Way-sized galaxies, carried out with the magnetohydrodynamic code AREPO. At redshift zero, about 70 per cent of our galactic discs show strong vertical patterns, with amplitudes that can exceed 2 kpc. Half of these are typical 'integral sign' warps. The rest are oscillations similar to those observed in the Milky Way. Such structures are thus expected to be common. The associated mean vertical motions can be as large as 30 km s-1. Cold disc gas typically follows the vertical patterns seen in the stars. These perturbations have a variety of causes: close encounters with satellites, distant fly-bys of massive objects, accretion of misaligned cold gas from halo infall or from mergers. Tidally induced vertical patterns can be identified in both young and old stellar populations, whereas those originating from cold gas accretion are seen mainly in the younger populations. Galaxies with regular or at most weakly perturbed discs are usually, but not always, free from recent interactions with massive companions, although we have one case where an equilibrium compact disc reforms after a merger.
Directory of Open Access Journals (Sweden)
Raynal Ramadhan Gobel
2014-03-01
Full Text Available Dalam sistem komunikasi nirkabel, salah satu permasalahan yang dihadapi adalah multipath fading. Hal ini mengakibatkan level daya yang bervariasi pada penerima sehingga terjadi outage ketika mengalami fading. Dalam lingkungan indoor, hal ini lebih sering terjadi karena hampir tidak ada line-of-sight antara pemancar dan penerima. Efek kanal multipath bisa diatasi dengan sistem komunikasi SIMO (Single-Input Multiple-Output. Sinyal yang diterima diolah menggunakan beberapa metode seperti Selection dan Maximal Ratio Combining dengan jumlah antena di penerima lebih dari satu. Implementasi juga bisa dilakukan pada WARP (Wireless Open-Access Research Platform yang merupakan salah satu jenis SDR (Software Defined Radio. Modul tersebut digunakan sebagai pemancar dan penerima pada pengukuran kualitas performansi SIMO pada lingkungan indoor dengan metode-metode combining. Hasil unjuk kerja dibandingkan terhadap sistem SISO (Single-Input Single-Output. Hasil dari implementasi dan pengukuran pada penelitian ini menunjukan bahwa, dalam lingkungan indoor pada kondisi tertentu, sistem SIMO dengan metode selection combining memiliki diversity gain 2.3–2.5 dB, sedangkan maximal ratio combining memiliki diversity gain 2.5–4.6 dB lebih baik daripada SISO pada kondisi BER .
Electroweak symmetry breaking without a Higgs boson in warped backgrounds constraints and signatures
Davoudiasl, H; Lillie, Benjamin Huntington; Rizzo, T G; 10.1103/PhysRevD.70.015006
2004-01-01
A warped 5-dimensional SU(2)$_L \\times SU(2)_R \\times$ U(1)$_{B-L}$ model has been recently proposed to implement electroweak symmetry breaking through boundary conditions, without the presence of a Higgs boson. This proposal is based on the Randall-Sundrum hierarchy solution. We use precision electroweak data to constrain the general parameter space of this model. Our analysis includes independent $L$ and $R$ gauge couplings, radiatively induced boundary gauge kinetic terms, and all higher order corrections from the curvature of the 5-d space. We show that this setup can be brought into good agreement with the precision electroweak data for typical values of the parameters. However, this set of parameters leads to violation of unitarity in gauge boson scattering, and hence this model is excluded in its present form. Assuming that unitarity can be restored in a modified version of this scenario, we consider the collider signatures. It is found that new spin-1 states will be observed at the LHC and measurement...
The Performance Of SISO In Wireless Open-Access Research Platform (WARP) Using QAM Modulation
Putri Hapsari, Jenny; Anisah, Ida
2017-04-01
This paper shows the implementation of SISO communication system using QAM modulation in WARP. The performance of the proposed system is evaluated in terms of Bit-Error-Rate (BER) for different M-array level: 4, 8, and 16 in indoor and outdoor environments, both using LOS condition. In the analysis results, SISO performance with 4-QAM modulation achieves better performance compared to 8-QAM and 16-QAM for both environments. Meanwhile, SISO performance with QAM modulation in outdoor environment achieves better results compared to indoor environment for different M-array level. In indoor environment with transmitted power -26 dBm, BER achieved for 4-QAM, 8-QAM, and 16-QAM are 1.33 × 10-4, 2.078 × 10-2, and 8.76 × 10-2, respectively. While in outdoor environment with the same transmitted power, BER achieved for 4-QAM, 8-QAM, and 16-QAM are 0, 1.497 × 10-2 and 5.928 × 10-2, respectively. SISO performance using M-QAM modulation is better than using M-PSK modulation.
Warped C80H30 nanographene as a chemical sensor for CO gas: DFT studies
Jameh-Bozorghi, Saeed; Soleymanabadi, Hamed
2017-02-01
In 2013, synthesis of a grossly warped nanographene (C80H30, NG) which was reported in Nature Chemistry opens a new avenue in carbonaceous nanomaterial research. Here we investigated the chemical reactivity and electronic sensitivity of this NG to carbon monoxide (CO) gas, using density functional theory calculations. It was found that the CO molecule prefers to be added to a C-C bond at the center of NG similarly to the [ 2 + 2] addition. The calculated adsorption energy which is about -10.92 kJ/mol is accompanied by a natural bond orbitals (NBO) charge transfer of 0.21 e from the NG to the CO molecule. Unlike the graphene, the electronic properties of NG are significantly affected by the CO adsorption. After the CO adsorption, the electrical conductivity of the NG is considerably increased which can be converted to an electrical signal. Thus, it is concluded that the NG may be a potential compound for the CO chemical sensors for which the pristine graphene is not appropriate. We demonstrated that by increasing the concentration of the CO molecules the electrical conductivity is increased more. Also, a short recovery time of about 83 ps is predicted for NG sensor.
Collider Signals Of Top Quark Flavor Violation From A Warped ExtraDimension
Energy Technology Data Exchange (ETDEWEB)
Agashe, Kaustubh; Perez, Gilad; Soni, Amarjit
2006-08-29
We study top quark flavor violation in the framework of a warped extra dimension with the Standard Model (SM) fields propagating in the bulk. Such a scenario provides solutions to both the Planck-weak hierarchy problem and the flavor puzzle of the SM without inducing a flavor problem. We find that, generically, tcZ couplings receive a huge enhancement, in particular the right handed ones can be {Omicron}(1%). This results in BR (t {yields} cZ) at or above the sensitivity of the Large Hadron Collider (LHC). At the International Linear Collider (ILC), single top production, via e{sup +}e{sup -} {yields} t{bar c}, can be a striking signal for this scenario. In particular, it represents a physics topic of critical importance that can be explored even with a relatively low energy option, close to the tc threshold. At both the LHC and the ILC, angular distributions can probe the above prediction of dominance of right-handed couplings.
Delta F=2 Observables and Fine-Tuning in a Warped Extra Dimension with Custodial Protection
Blanke, Monika; Duling, Bjoern; Gori, Stefania; Weiler, Andreas
2009-01-01
We present a complete study of Delta S = 2 and Delta B = 2 processes in warped extra dimensional models with a custodial protection of Z b_L anti-b_L, including epsilon_K, Delta M_K, Delta M_s, Delta M_d, A_SL^q, Delta Gamma_q, A_CP(B_d -> psi K_S) and A_CP(B_s -> psi phi). These processes are affected by tree level contributions from Kaluza-Klein gluons and new heavy electroweak gauge bosons Z_H and Z', with the latter implied by the custodial protection mechanism. We confirm recent findings that the fully anarchic approach where all the hierarchies in quark masses and weak mixing angles are geometrically explained seems implausible and we confirm that the KK mass scale M_KK generically has to be at least ~ 20TeV to satisfy the epsilon_K constraint. We point out, however, that there exist regions in parameter space with only modest fine-tuning in the 5D Yukawa couplings which satisfy all existing Delta F = 2 and electroweak precision constraints for scales M_KK ~ 3TeV in reach of the LHC. Simultaneously we f...
Modulus stabilisation in a backreacted warped geometry model via Goldberger-Wise mechanism
Das, Ashmita; SenGupta, Soumitra
2016-01-01
In the context of higher dimensional braneworld scenario, the stabilisation of extra dimensional modulus is an essential requirement for resolving the gauge hierarchy problem in the context of Standard Model of elementary particle Physics. For Randall-Sundrum (RS) warped extra dimensional model, Goldberger and Wise (GW) proposed a much useful mechanism to achieve this using a scalar field in the bulk spacetime ignoring the effects of backreaction of the scalar field on the background metric. In this article we examine the influence of the backreaction of the stabilising field on the stabilisation condition as well as that on the Physics of the extra dimensional modulus namely radion. In particular we obtain the modifications of the mass and the coupling of the radion with the Standard Model (SM) matter fields on the TeV brane due to backreaction effect. Our calculation also brings out an important equivalence between the treatments followed by Csaki et.al. in \\cite{kribs} and Goldberger-Wise in \\cite{GW1,GW_r...
SOLUTION OF GENERALIZED COORDINATE FOR WARPING FOR NATURALLY CURVED AND TWISTED BEAMS
Institute of Scientific and Technical Information of China (English)
虞爱民; 易明
2004-01-01
A theoretical method for static analysis of naturally curved and twisted beams under complicated loads was presented, with special attention devoted to the solving process of governing equations which take into account the effects of torsion-related warping as well as transverse shear deformations. These governing equations, in special cases, can be readily solved and yield the solutions to the problem. The solutions can be used for the analysis of the beams, including the calculation of various internal forces, stresses, strains and displacements. The present theory will be used to investigate the stresses and displacements of a plane curved beam subjected to the action of horizontal and vertical distributed loads. The numerical results obtained by the present theory are found to be in very good agreement with the results of the FEM results. Besides, the present theory is not limited to the beams with a double symmetric cross-section, it can also be extended to those with arbitrary cross-sectional shape.
Vakanski, A; Mantegh, I; Irish, A; Janabi-Sharifi, F
2012-08-01
The main objective of this paper is to develop an efficient method for learning and reproduction of complex trajectories for robot programming by demonstration. Encoding of the demonstrated trajectories is performed with hidden Markov model, and generation of a generalized trajectory is achieved by using the concept of key points. Identification of the key points is based on significant changes in position and velocity in the demonstrated trajectories. The resulting sequences of trajectory key points are temporally aligned using the multidimensional dynamic time warping algorithm, and a generalized trajectory is obtained by smoothing spline interpolation of the clustered key points. The principal advantage of our proposed approach is utilization of the trajectory key points from all demonstrations for generation of a generalized trajectory. In addition, variability of the key points' clusters across the demonstrated set is employed for assigning weighting coefficients, resulting in a generalization procedure which accounts for the relevance of reproduction of different parts of the trajectories. The approach is verified experimentally for trajectories with two different levels of complexity.
Higgs Bosons in Warped Space, from the Bulk to the Brane
Frank, Mariana; Toharia, Manuel
2013-01-01
In the context of warped extra-dimensional models with all fields propagating in the bulk, we address the phenomenology of a bulk scalar Higgs boson, and calculate its production cross section at the LHC as well as its tree-level effects on mediating flavor changing neutral currents. We perform the calculations based on two different approaches. First, we compute our predictions analytically by considering all the degrees of freedom emerging from the dimensional reduction (the infinite tower of Kaluza Klein modes (KK)). In the second approach, we perform our calculations numerically by considering only the effects caused by the first few KK modes, present in the 4-dimensional effective theory. In the case of a Higgs leaking far from the brane, both approaches give the same predictions as the effects of the heavier KK modes decouple. However, as the Higgs boson is pushed towards the TeV brane, the two approaches seem to be equivalent only when one includes heavier and heavier degrees of freedom (which do not s...
Gravitons in multiply warped scenarios: At 750 GeV and beyond
Arun, Mathew Thomas; Saha, Pratishruti
2017-06-01
The search for extra dimensions has so far yielded no positive results at the LHC. Along with the discovery of a 125 {GeV} Higgs boson, this implies a moderate degree of fine-tuning in the parameter space of the Randall-Sundrum model. Within a six-dimensional warped compactification scenario, with its own interesting phenomenological consequences, the parameters associated with the additional spatial direction can be used to eliminate the need for fine-tuning. We examine the constraints on this model due to the 8 {TeV} LHC data and survey the parameter space that can be probed at the 14 {TeV} run of the LHC. We also identify the region of parameter space that is consistent with the recently reported excess in the diphoton channel in the 13 {TeV} data. Finally, as an alternative explanation for the observed excess, we discuss a scenario with brane-localized Einstein-Hilbert terms with Standard Model fields in the bulk.
Larwood, J D; Papaloizou, J C B; Terquem, C
1996-01-01
We present the results of non linear, hydrodynamic simulations, in three dimensions, of the tidal perturbation of accretion discs in binary systems where the orbit is circular and not necessarily coplanar with the disc mid-plane. The accretion discs are assumed to be geometrically thin, and of low mass relative to the stellar mass so that they are governed by thermal pressure and viscosity, but not self-gravity. The parameters that we consider in our models are the ratio of the orbital distance to the disc radius, D/R, the binary mass ratio, the initial inclination angle between the orbit and disc planes and the Mach number in the outer parts of the unperturbed disc. For binary mass ratios of around unity and D/R in the range 3 to 4, we find that the global evolution of the discs is governed primarily by the value of the Mach number. For relatively low Mach numbers (i.e. 10 to 20) we find that the discs develop a mildly warped structure, are tidally truncated, and undergo a near rigid body precession at a rat...
Wang, T.
2017-05-26
Elastic full waveform inversion (EFWI) provides high-resolution parameter estimation of the subsurface but requires good initial guess of the true model. The traveltime inversion only minimizes traveltime misfits which are more sensitive and linearly related to the low-wavenumber model perturbation. Therefore, building initial P and S wave velocity models for EFWI by using elastic wave-equation reflections traveltime inversion (WERTI) would be effective and robust, especially for the deeper part. In order to distinguish the reflection travletimes of P or S-waves in elastic media, we decompose the surface multicomponent data into vector P- and S-wave seismogram. We utilize the dynamic image warping to extract the reflected P- or S-wave traveltimes. The P-wave velocity are first inverted using P-wave traveltime followed by the S-wave velocity inversion with S-wave traveltime, during which the wave mode decomposition is applied to the gradients calculation. Synthetic example on the Sigbee2A model proves the validity of our method for recovering the long wavelength components of the model.
Hawking Radiation of Warped Anti de Sitter and Rotating Hairy Black Holes with Scalar Hair
Gursel, H
2015-01-01
This thesis mainly focuses on the Hawking radiation (HR) evacuating from the surface of the objects that have earned a reputation as the most extraordinary objects existing so far; the black holes (BHs). Throughout this study, quantum tunneling (QT) process serves as the model for the HR of scalar, vector and Dirac particles. The scalar and Dirac particles are anticipated to be tunneling through the horizon of rotating scalar hairy black holes (RHSBHs); whilst the vector particles are associated with a rotating warped anti de-Sitter black hole (WAdS3BH) embedded in a (2+1) dimensional fabric. It is no coincidence that for all three cases; the standard HT expression is derived. Additionally, the engagement of conformal field theory (CFT) with anti de-Sitter (AdS) space presents itself to the reader and the methodologies of Klein-Gordon equation (KGE), Dirac equation and Proca equations (PEs) are introduced. For all three cases, Hamilton-Jacobi (HJ) approach is used, together with Wentzel-Kramers-Brillouin (WKB...
Warping, Extra Dimensions and a Slice of AdS_d
McDonald, Kristian L
2009-01-01
Inspired by the Randall-Sundrum (RS) framework we consider a number of phenomenologically relevant model building questions on a slice of compactified AdS_d for d >5. Such spaces are interesting as they enable one to realize the weak scale via warping. We perform the Kaluza-Klein (KK) reduction for gravitons and bulk vectors in these spaces and for the case of AdS_6 consider the KK spectrum of gauge-scalars. We further obtain the KK towers for bulk fermions on a slice of AdS_7 and AdS_9 and show that the RS approach to flavor generalizes to these spaces with the localization of chiral zero mode fermions controlled by their bulk Dirac mass parameters. However for the phenomenologically interesting case where the transverse radius is R^{-1}\\sim TeV we show that bulk Standard Model fields are not viable due to a resulting volume suppression of the gauge coupling constants. A similar suppression occurs for the case of UV localization. Thus it seems that the Standard Model fields should be confined to the infrared...
异经异纬卡其织物的生产实践%Experience of Producing Different Warp and Weft Khaki Fabric
Institute of Scientific and Technical Information of China (English)
黄峰
2011-01-01
Production processing and key technology measures of using different warp and weft khaki fabric were discussed. Through analyzing the material porperty, product specifications, fabric style, the cheese tension uniformity should be improved in doubling, high predrying temperature and low maindrying temperature should be adopted in different warps sizing, the overlap between two kinds of warp should be insulated by fabric in beam unwinding to prevent warp mixed into another warp, the processing of smaller shedding, suitable back-bearer height, earlier shedding and greater tension should be set in weaving, warp shed line and picking pressure should be set suitably, the loom efficiency of weaving different warp and weft khaki fabric can be ensured over 92％ , the export qualification rate can be reached over 98％.%探讨异经异纬卡其织物的生产工艺和关键技术措施.通过分析织物的原料性能、产品规格、布面风格,并线时要提高并线筒纱张力的一致性;在浆纱工序异经同浆时要采取"高预烘,低主烘"的工艺配置,经轴在退绕时两种经纱重叠区用布隔离,防止断头经纱混入另一种经纱里造成错号;在织造工序采用"小开口,中后梁,早开口,大张力"工艺配置,合理配置经位置线和引纬气压,可确保该系列织物的织机效率达92%以上,出口合格率达98%以上.
Kochemasov, G. G.
2008-09-01
probable. Very regular cross-cutting wavy forms hundred and thousand kilometers long have a spacing between ridges or grooves about 1-2 km (?) (PIA03555, PIA03566, PIA03567, PIA03568 ) or 10-20 km (PIA08454) -so called "cat scratches". The most long and wide ridge-groove system observed up to now (PIA08454 - a swath 6150 km long, 1120 km wide, almost a half length of the great planetary circle!) has the ridge-to-ridge spacing about 10-20 km; a width of ridges and grooves is nearly equal with variations to both sides; ridges are more bright, grooves are more dark; intersections of the ridge-groove systems creates chains of roundish features ("craters") of characteristic size (Fig. 3, 4). Observed wavy systems resemble dunes only at the first glance but actually are deformations of the ice-methane crust by very fine inertia-gravity waves aroused by the satellite movement in non-round elliptical keplerian orbit [3]. This movement with periodically changing accelerations arouse inertia-gravity forces and waves warping any celestial body notwithstanding its size, mass, density, chemical composition or physical state. In rotating bodies (but all bodies rotate!) these warping waves have a stationary character and 4 cross-cutting directions- ortho- and diagonal - producing uplifted (+), subsided (-) and neutral (0) tectonic blocks. Wavelengths are different but tied as harmonics. The fundamental wave1 produces ubiquitous tectonic dichotomy -two segments (2πR-structure), the first harmonics wave2 produces tectonic sectors (πR-structures) [1]. This structurization is adorned by individual for any body waves whose lengths are inversely proportional to their orbital frequencies: higher frequency - smaller waves and, vice versa, lower frequency - larger waves. These waves produce tectonic granules. There is a row of increasing granule sizes strictly tied to orbital frequencies: Mercury πR/16, Venus πR/6, Earth πR/4, Mars πR/2, asteroids πR/1. In this row Titan with its orbital
Groundwater similarity across a watershed derived from time-warped and flow-corrected time series
Rinderer, M.; McGlynn, B. L.; van Meerveld, H. J.
2017-05-01
Information about catchment-scale groundwater dynamics is necessary to understand how catchments store and release water and why water quantity and quality varies in streams. However, groundwater level monitoring is often restricted to a limited number of sites. Knowledge of the factors that determine similarity between monitoring sites can be used to predict catchment-scale groundwater storage and connectivity of different runoff source areas. We used distance-based and correlation-based similarity measures to quantify the spatial and temporal differences in shallow groundwater similarity for 51 monitoring sites in a Swiss prealpine catchment. The 41 months long time series were preprocessed using Dynamic Time-Warping and a Flow-corrected Time Transformation to account for small timing differences and bias toward low-flow periods. The mean distance-based groundwater similarity was correlated to topographic indices, such as upslope contributing area, topographic wetness index, and local slope. Correlation-based similarity was less related to landscape position but instead revealed differences between seasons. Analysis of variance and partial Mantel tests showed that landscape position, represented by the topographic wetness index, explained 52% of the variability in mean distance-based groundwater similarity, while spatial distance, represented by the Euclidean distance, explained only 5%. The variability in distance-based similarity and correlation-based similarity between groundwater and streamflow time series was significantly larger for midslope locations than for other landscape positions. This suggests that groundwater dynamics at these midslope sites, which are important to understand runoff source areas and hydrological connectivity at the catchment scale, are most difficult to predict.
A New Fate of a Warped 5D FLRW Model with a U(1) Scalar Gauge Field
Slagter, Reinoud Jan; Pan, Supriya
2016-09-01
If we live on the weak brane with zero effective cosmological constant in a warped 5D bulk spacetime, gravitational waves and brane fluctuations can be generated by a part of the 5D Weyl tensor and carries information of the gravitational field outside the brane. We consider on a cylindrical symmetric warped FLRW background a U(1) self-gravitating scalar field coupled to a gauge field without bulk matter. It turns out that brane fluctuations can be formed dynamically, due to the modified energy-momentum tensor components of the scalar-gauge field ("cosmic string"). As a result, we find that the late-time behavior could significantly deviate from the standard evolution of the universe. The effect is triggered by the time-dependent warpfactor with two branches of the form ± 1/√{τ r}√{(c_1e^{√{2τ } t}+c_2e^{-√{2τ } t})(c_3e^{√{2τ } r}+c_4e^{-√{2τ } r})} ( with τ , c_i constants) and the modified brane equations comparable with a dark energy effect. This is a brane-world mechanism, not present in standard 4D FLRW, where the large disturbances are rapidly damped as the expansion proceed. Because gravity can propagate in the bulk, the cosmic string can build up a huge angle deficit (or mass per unit length) by the warpfactor and can induce massive KK-modes felt on the brane. Disturbances in the spatial components of the stress-energy tensor cause cylindrical symmetric waves, amplified due to the presence of the bulk space and warpfactor. They could survive the natural damping due to the expansion of the universe. It turns out that one of the metric components becomes singular at the moment the warp factor develops an extremum. This behavior could have influence on the possibility of a transition from acceleration to deceleration or vice versa.
Shen, Shiqi; Zhu, Zhifeng; Liu, Fengdan
2016-03-15
An attempt has been made to reveal the effect of amphoteric poly(2-acryloyloxyethyl trimethyl ammonium chloride-co-acrylic acid) [P(ATAC-co-AA)] branches grafted onto the backbones of starch upon the adhesion-to-cotton, film properties, and desizability of maize starch for cotton warp sizing. Starch-g-poly[(2-acryloyloxyethyl trimethyl ammonium chloride)-co-(acrylic acid) [S-g-P(ATAC-co-AA)] was prepared by the graft copolymerization of 2-acryloyloxyethyl trimethyl ammonium chloride (ATAC) and acrylic acid (AA) with acid-converted starch (ACS) in aqueous medium using Fe(2+)-H2O2 initiator. The adhesion was evaluated in term of bonding strength according to the FZ/T 15001-2008 whereas the film properties considered included tensile strength, work and percentage elongation at break. The evaluation was undertaken through the comparison of S-g-P(ATAC-co-AA) with ACS, starch-g-poly(acrylic acid), and starch-g-poly(2-acryloyloxyethyl trimethyl ammonium chloride). It was found that the amphoteric branch was able to significantly improve the adhesion and mitigate the brittleness of starch film. Zeta potential of cooked S-g-P(ATAC-co-AA) paste, depending on the mole ratio of ATAC to AA units on P(ATAC-co-AA) branches, had substantial effect on the adhesion and desizability. Increasing the mole ratio raised the potential, which favored the adhesion but disfavored the removal of S-g-P(ATAC-co-AA) from sized cotton warps. Electroneutral S-g-P(ATAC-co-AA) was superior to negatively grafted starch in adhesion and to positively grafted starch in desizability. Generally, it showed better sizing property than ACS, starch-g-poly(acrylic acid), and starch-g-poly(2-acryloyloxyethyl trimethyl ammonium chloride), and had potential in the application of cotton warp sizing.
Energy Technology Data Exchange (ETDEWEB)
Veiga, Catarina, E-mail: catarina.veiga.11@ucl.ac.uk; Royle, Gary [Radiation Physics Group, Department of Medical Physics and Biomedical Engineering, University College London, London WC1E 6BT (United Kingdom); Lourenço, Ana Mónica [Radiation Physics Group, Department of Medical Physics and Biomedical Engineering, University College London, London WC1E 6BT, United Kingdom and Acoustics and Ionizing Radiation Team, National Physical Laboratory, Teddington TW11 0LW (United Kingdom); Mouinuddin, Syed [Department of Radiotherapy, University College London Hospital, London NW1 2BU (United Kingdom); Herk, Marcel van [Department of Radiation Oncology, The Netherlands Cancer Institute, Amsterdam 1066 CX (Netherlands); Modat, Marc; Ourselin, Sébastien; McClelland, Jamie R. [Centre for Medical Image Computing, Department of Medical Physics and Biomedical Engineering, University College London, London WC1E 6BT (United Kingdom)
2015-02-15
Purpose: The aims of this work were to evaluate the performance of several deformable image registration (DIR) algorithms implemented in our in-house software (NiftyReg) and the uncertainties inherent to using different algorithms for dose warping. Methods: The authors describe a DIR based adaptive radiotherapy workflow, using CT and cone-beam CT (CBCT) imaging. The transformations that mapped the anatomy between the two time points were obtained using four different DIR approaches available in NiftyReg. These included a standard unidirectional algorithm and more sophisticated bidirectional ones that encourage or ensure inverse consistency. The forward (CT-to-CBCT) deformation vector fields (DVFs) were used to propagate the CT Hounsfield units and structures to the daily geometry for “dose of the day” calculations, while the backward (CBCT-to-CT) DVFs were used to remap the dose of the day onto the planning CT (pCT). Data from five head and neck patients were used to evaluate the performance of each implementation based on geometrical matching, physical properties of the DVFs, and similarity between warped dose distributions. Geometrical matching was verified in terms of dice similarity coefficient (DSC), distance transform, false positives, and false negatives. The physical properties of the DVFs were assessed calculating the harmonic energy, determinant of the Jacobian, and inverse consistency error of the transformations. Dose distributions were displayed on the pCT dose space and compared using dose difference (DD), distance to dose difference, and dose volume histograms. Results: All the DIR algorithms gave similar results in terms of geometrical matching, with an average DSC of 0.85 ± 0.08, but the underlying properties of the DVFs varied in terms of smoothness and inverse consistency. When comparing the doses warped by different algorithms, we found a root mean square DD of 1.9% ± 0.8% of the prescribed dose (pD) and that an average of 9% ± 4% of
缥缈变化的“宋”罗%Leno weaving techniques in Song Dynasty
Institute of Scientific and Technical Information of China (English)
罗群
2012-01-01
回顾了罗的变化历史及其组织结构和织造技术的演化,分析了南宋黄昇墓中出土的各种花罗组织结构多样性,重点探讨了二经绞平纹花罗、二经绞浮纬花罗、三经绞平纹花罗、三经绞斜纹花罗、三经绞隐纹花罗等在小花楼束综提花机上的装造形式、织造工艺和操作程序,为再现古代提花织罗技术的奇巧及保护和传承这项独特的丝织技艺提供技术支持.%This study introduced the evolution, weave structure and weaving technique of leno fabric and analyzed the weave diversity of patterned lenos excavated from "Huang Sheng" tomb of Song Dynasty. The loom style, weaving handicraft and operation sequence in the jacquard of the patterned lenos consisting of two warp ends with pattern woven by tabby, two warp ends with pattern woven with float weft, three warp ends with pattern woven by tabby, three warp ends with pattern woven by twill 1/2 and three warp ends with ground woven by leno and pattern woven by leno were emphatically researched. This study will provide the technical support for the reappearance, protection and inheritance of the ancient silk leno weaving techniques.
Energy Technology Data Exchange (ETDEWEB)
Albrecht, Michaela E.
2010-08-16
The minimal-flavour-violating (MFV) hypothesis considers the Standard Model (SM) Yukawa matrices as the only source of flavour violation. In this work, we promote their entries to dynamical scalar spurion fields, using an effective field theory approach, such that the maximal flavour symmetry (FS) of the SM gauge sector is formally restored at high energy scales. The non-vanishing vacuum expectation values of the spurions induce a sequence of FS breaking and generate the observed hierarchy in the SM quark masses and mixings. The fact that there exists no explanation for it in the SM is known as the flavour puzzle. Gauging the non-abelian subgroup of the spontaneously broken FS, we interpret the associated Goldstone bosons as the longitudinal degrees of freedom of the corresponding massive gauge bosons. Integrating out the heavy Higgs modes in the Yukawa spurions leads directly to flavour-changing neutral currents (FCNCs) at tree level. The coefficients of the effective four-quark operators, resulting from the exchange of heavy flavoured gauge bosons, strictly follow the MFV principle. On the other hand, the Goldstone bosons associated with the global abelian symmetry group behave as weakly coupled axions which can be used to solve the strong CP problem within a modified Peccei-Quinn formalism. Models with a warped fifth dimension contain five-dimensional (5D) fermion bulk mass matrices in addition to their 5D Yukawa matrices, which thus represent an additional source of flavour violation beyond MFV. They can address the flavour puzzle since their eigenvalues allow for a different localisation of the fermion zero mode profiles along the extra dimension which leads to a hierarchy in the effective four-dimensional (4D) Yukawa matrices. At the same time, the fermion splitting introduces non-universal fermion couplings to Kaluza-Klein (KK) gauge boson modes, inducing tree-level FCNCs. Within a Randall-Sundrum model with custodial protection (RSc model) we carefully work
Long-term Properties of Accretion Disks in X-ray Binaries II. Stability of Radiation-Driven Warping
Clarkson, W I; Coe, M J; Laycock, S
2003-01-01
A significant number of X-ray binaries are now known to exhibit long-term ``superorbital'' periodicities on timescales of $\\sim$ 10 - 100 days. Several physical mechanisms have been proposed that give rise to such periodicities, in particular warping and/or precession of the accretion disk. Recent theoretical work predicts the stability to disk warping of X-ray binaries as a function of the mass ratio, binary radius, viscosity and accretion efficiency, and here we examine the constraints that can be placed on such models by current observations. In paper I we used a dynamic power spectrum (DPS) analysis of long-term X-ray datasets (CGRO, RXTE), focusing on the remarkable, smooth variations in the superorbital period exhibited by SMC X-1. Here we use a similar DPS analysis to investigate the stability of the superorbital periodicities in the neutron star X-ray binaries Cyg X-2, LMC X-4 and Her X-1, and thereby confront stability predictions with observation. We find that the period and nature of superorbital v...
Dirac neutrinos with S4 flavor symmetry in warped extra dimensions
Ding, Gui-Jun; Zhou, Ye-Ling
2013-11-01
We present a warped extra dimension model with the custodial symmetry SU(2×SU(2×U(1×PLR based on the flavor symmetry S4×Z2×Z2', and the neutrinos are taken to be Dirac particles. At leading order, the democratic lepton mixing is derived exactly, and the high-dimensional operators introduce corrections of order λc to all the three lepton mixing angles such that agreement with the experimental data can be achieved. The neutrino mass spectrum is predicted to be of the inverted hierarchy and the second octant of θ23 is preferred. We suggest the modified democratic mixing, which is obtained by permuting the second and the third rows of the democratic mixing matrix, should be a good first order approximation to understanding sizable θ13 and the first octant of θ23. The constraints on the model from the electroweak precision measurements are discussed. Furthermore, we investigate the lepton mixing patterns for all the possible residual symmetries Gν and Gl in the neutrino and charged lepton sectors, respectively. For convenience, we work in the base in which m≡mlml† is diagonal, where ml is the charged lepton mass matrix. It is easy to see that the symmetry transformation matrix Gl, which is determined by the condition Gl†mGl=m, is a diagonal and non-degenerate 3×3 phase matrix. In the case that neutrinos are Majorana particles, the light neutrino mass matrix for DC mixing is of the form mνDC=UDC*diag(m1,m2,m3)UDC†. The symmetry transformations Gi, which satisfy GiTmνDCGi=mνDC, are determined to be G1=+u1u1†-u2u2†-u3u3†, G2=-u1u1†+u2u2†-u3u3† and G3=-u1u1†-u2u2†+u3u3† besides the identity transformation, where ui is the ith column of UDC. They satisfy Gi2=1, GiGj=GjGi=Gk(i≠j≠k). Consequently the symmetry group of the neutrino mass matrix mνDC is the Klein four group K4≅Z2×Z2. Denoting the underlying family symmetry group at high energies as G, then the symmetry transformations Gl and Gi should be the elements of G. In the
风电用多轴向经编织物的结构设计%THE STRUCTURE DESIGN OF MULTIAXIAL WARP KNITTED FABRIC IN WIND POWER GENERATION
Institute of Scientific and Technical Information of China (English)
王雪芳; 丛洪莲; 张爱军
2012-01-01
多轴向经编技术是一种新型的多头衬纬编织技术,该技术生产的多轴向经编织物具有尺寸稳定、延伸率小等特点,在产业用领域已受到广泛的重视.本文介绍了多轴向经编织物的结构与性能以及纱层方向的表示方法,从风力发电机叶片结构、多轴向经编织物材料、叶片受力分析、制造工艺方面详细介绍了多轴向经编织物在风力发电机叶片中的应用,以双斜向经编织物为例,采用WKCAD设计仿真并分析.%Multiaxial warp knitted technology is the way that can lay-in more weft at the same time, the mul-tiaxial warp knitted fabric produced by this technology has stable size, small elongation and other characteristics, has been appreciated in the industrial field extensively. This paper introduces the structure and performance of multiaxial warp knitted fabric and the method to show the direction of the lay-in yarn, introduces the application of multiaxial warp knitted fabric in wind power generation in detail including the structure of the blade, the materials, the stress analysis of the blade and the manufacturing process. As a example of biaxial warp knitted fabric, design and analysis it based on WKCAD.
Study on the Preparation of Allyl-modified Starch in Isopropyl/Water Medium for Warp Sizing
Institute of Scientific and Technical Information of China (English)
LI Man-li; ZHU Zhi-feng; ZHANG Long-qiu
2008-01-01
A new method for the pretreatment of starch by etherification was developed to eliminate the problems of lower grafting efficiency associated with the preparation of starch graft copolymers as warp sizing agents.The etherification of starch with allyl chloride was investigated in order to effectively enhance the reaction efficiency.The technological variables of the reaction considered for evaluating the etherification included sodium hydroxide amount,water content in water-isopropyi alcohol medium,allyl cldoride concentration,reaction temperature and reaction time.The experimental result demonstrated that the variables considered showed evident effect on the reaction efficiency.For the etherification,a condition of 20% for the water content,1.5:1 for the molar ratio of sodium hydroxide to allyl chloride.and at 30℃ under 24h reaction is Sufficient to retain the reaction efficiency above 50%.Furthermore,a contrast test demonstrated that the graft efficiency can be increased with the etherification pretreatment.
Liberati, Stefano
2016-01-01
While General Relativity ranks undoubtedly among the best physics theories ever developed, it is also among those with the most striking implications. In particular, General Relativity admits solutions which allow faster than light motion and consequently time travel. Here we shall consider a "pre-emptive" chronology protection mechanism that destabilises superluminal warp drives via quantum matter back-reaction and hence forbids even the conceptual possibility to use these solutions for building a time machine. This result will be considered both in standard quantum field theory in curved spacetime as well as in the case of a quantum field theory with Lorentz invariance breakdown at high energies. Some lessons and future perspectives will be finally discuss.
Energy Technology Data Exchange (ETDEWEB)
Bernardini, A.E., E-mail: alexeb@ufscar.br; Bertolami, O., E-mail: orfeu.bertolami@fc.up.pt
2013-10-07
An equivalence between Born–Infeld and effective real scalar field theories for brane structures is built in some specific warped space–time scenarios. Once the equations of motion for tachyon fields related to the Born–Infeld action are written as first-order equations, a simple analytical connection with a particular class of real scalar field superpotentials can be found. This equivalence leads to the conclusion that, for a certain class of superpotentials, both systems can support identical thick brane solutions as well as brane structures described through localized energy densities, T{sub 00}(y), in the 5th dimension, y. Our results indicate that thick brane solutions realized by the Born–Infeld cosmology can be connected to real scalar field brane scenarios which can be used to effectively map the tachyon condensation mechanism.
Pasquini, Pedro; Valle, J W F
2016-01-01
Here we study the pattern of neutrino oscillations emerging from a previously proposed warped model construction incorporating $\\Delta(27)$ flavor symmetry. In addition to a complete description of fermion masses, the model predicts the lepton mixing matrix in terms of two parameters. The good measurement of $\\theta_{13}$ makes these two parameters nearly proportional, leading to an approximate one-parameter description of neutrino oscillations. There is a sharp fourfold degenerate correlation between $\\delta_{CP}$ and the atmospheric mixing angle $\\theta_{23}$, so that maximal $\\theta_{23}$ also implies maximal leptonic CP violation. The predicted electron neutrino and anti-neutrino appearance probabilities indicate that the model should be tested at the T2K, NO$\
Institute of Scientific and Technical Information of China (English)
张俊利
2014-01-01
The paper discusses the key techniques for producing mini-jacquard woven fabric using blended yarns between ultra-fine polyester and cotton, hemp and other fibers as warps and wefts. By analyzing fabric style and difficulties in production, it suggests the rational process route and optimized parameters for warping, sizing and weaving processes. The resulted fabric has special stripped structure and unique look, offering reference for developing and producing high-grade apparel fabric.%探讨了超细旦涤纶与棉、汉麻等异经异纬提花织物生产技术的要点。通过对该面料的织物风格以及生产难点进行分析，选择合理的工艺流程，优化整经、浆纱织造等工序的工艺参数。面料具有特殊的条形结构，风格独特，为高档服装面料的开发及生产提供参考。
A multivariate time-warping based classifier for gesture recognition with wearable strain sensors.
Giorgino, Toni; Tormene, Paolo; Quaglini, Silvana
2007-01-01
Conductive elastomer elements can be industrially embedded into garments to form unobtrusive strain sensing stripes. The present article outlines the structure of a strain-sensor based gesture detection algorithm. Current sensing prototypes include several dozens of sensors; their redundancy with respect to the limb's degrees of freedom, and other artifacts implied by this measurement technique, call for the development of novel robust multivariate pattern-matching techniques. The algorithm's construction is explained, and its performances are evaluated in the context of motor rehabilitation exercises for both two-class and multi-class tasks.
Currie, Thayne; Thalmann, Christian; Matsumura, Soko; Madhusudhan, Nikku; Burrows, Adam; Kuchner, Marc
2011-01-01
We present and analyze a new M' detection of the young exoplanet Beta Pictoris b from 2008 VLT/NaCo data at a separation of approx. = 4 AU and a high signal-to-noise rereduction of L' data taken in December 2Q09. Based on our orbital analysis, the planet's orbit is viewed almost perfectly edge-on (i approx. 89 degrees) and has a Saturn-like semimajor axis of 9.50AU(+3.93 AU)/-(1.7AU) . Intriguingly, the planet's orbit is aligned with the major axis of the outer disk (Omega approx.31 degrees) but probably misaligned with the warp/inclined disk at 80 AU often cited as a signpost for the planet's existence. Our results motivate new studies to clarify how Beta Pic b sculpts debris disk structures and whether a second planet is required to explain the warp/inclined disk
异经多纬双层织物的生产%Production of Two-layer Fabric with Different Warp and Multiple Weft
Institute of Scientific and Technical Information of China (English)
郭凯军; 刘渊民; 邓红卫
2012-01-01
Design and key points in producing two-layer fabric with different warp and multiple wefts were discussed. The differences between warp and weft were larger,the production difficulties were larger than that of traditional fabric,two kinds of warp tension should be controlled well in warping. Slub yarn was dyed in sizing process to ensure correct reed-in. In weaving process, weft-inserting pressure of main nozzle was adjusted properly, loom tension was increased properly, loom processing was optimized rationally to prevent weft movement in back and weft shrinkage et al After adjusting processing, loom efficiency can be reached above 87% , storage rate of first-class product can be reached above 99. 8% , design and production demands can be reached.%探讨异经多纬双层织物的设计与生产技术要点.针对织物经纬纱差异、生产难度比传统织物大的特点,整经工序要控制好两种经纱的张力；浆纱时对其中的竹节纱进行上色,确保穿筘工序按工艺排列正确穿筘；织造工序合理调节主喷嘴引纬气压,适当增加上机张力,合理调试上机工艺,防止反面纬纱游移、纬缩等疵点造成染整后布面风格与质量变差.通过对工艺进行调整后,织机效率达到87％以上,产品入库一等品率达99.8％以上,满足了设计及生产要求.
多系统经纱织物小样织机的研制%Development of Multisystem Warp Fabric Sample Loom
Institute of Scientific and Technical Information of China (English)
侯翠芳
2011-01-01
Structure,work principle and use effect of multisystem warp fabric sample loom were introduced.Moving guide needle device was set on multisystem warp fabric sample loom,guide needle bend down,guide needle traverse distance could be controlled,tension compensatory parts was set.Through weaving leno fabric and lapped fabric,it is proved that multisystem warp fabric could be woven on the one sample loom and the product could be changed simply.%介绍多系统经纱织物小样织机的结构、工作原理及使用效果.多系统经纱织物小样织机在钢筘上设置移动导针装置,导针向下弯折,导针横动距离可以控制,并设有张力补偿部件,通过试织纱罗织物和浮纹织物,证明多系统经纱织物小样织机可以在一台织机上实现多个系统经纱织物的试织,且变换品种简单方便.
Warped AdS6 × S 2 in Type IIB supergravity II: global solutions and five-brane webs
D'Hoker, Eric; Gutperle, Michael; Uhlemann, Christoph F.
2017-05-01
Motivated by the construction of holographic duals to five-dimensional superconformal quantum field theories, we obtain global solutions to Type IIB supergravity invariant under the superalgebra F (4) on a space-time of the form AdS6 × S 2 warped over a two-dimensional Riemann surface Σ. In earlier work, the general local solutions were expressed in terms of two locally holomorphic functions A ± on Σ and global solutions were sketched when Σ is a disk. In the present paper, the physical regularity conditions on the supergravity fields required for global solutions are implemented on A ± for arbitrary Σ. Global solutions exist only when Σ has a non-empty boundary ∂Σ. The differentials ∂ A ± are allowed to have poles only on ∂Σ and each pole corresponds to a semi-infinite ( p, q) five-brane. The construction for the disk is carried out in detail and the conditions for the existence of global solutions are articulated for surfaces with more than one boundary and higher genus.
Warped AdS{sub 6}×S{sup 2} in Type IIB supergravity I: local solutions
Energy Technology Data Exchange (ETDEWEB)
D’Hoker, Eric; Gutperle, Michael [Department of Physics and Astronomy, University of California Los Angeles,405 Hilgard Avenue, Los Angeles, CA 90095-1547 (United States); Karch, Andreas; Uhlemann, Christoph F. [Department of Physics, University of Washington,P.O. Box 351560, Seattle, WA 98195-1560 (United States)
2016-08-05
We investigate the existence of solutions with 16 residual supersymmetries to Type IIB supergravity on a space-time of the form AdS{sub 6}×S{sup 2} warped over a two-dimensional Riemann surface Σ. The SO(2,5)×SO(3) isometry extends to invariance under the exceptional Lie superalgebra F(4). In the present paper, we construct the general Ansatz compatible with these symmetries, derive the corresponding reduced BPS equations, and obtain their complete local solution in terms of two locally holomorphic functions A{sub ±} on Σ, subject to certain positivity and regularity conditions. Globally, (A{sub +},A{sub −}) are allowed to be multiple-valued on Σ and be holomorphic sections of a holomorphic bundle over Σ with structure group contained in SU(1,1)×ℂ. Globally regular solutions are expected to provide the near-horizon geometry of (p,q) 5-brane and 7-brane webs which are holographic duals to five-dimensional conformal field theories. A preliminary analysis of the positivity and regularity conditions will be presented here, leaving the construction of globally regular solutions to a subsequent paper.
Pad dyeing of nylon spandex warp knits%锦氨经编织物轧染工艺
Institute of Scientific and Technical Information of China (English)
刘建平; 岳仕芳; 田恬
2013-01-01
Continuous pad dyeing of nylon spandex warp knitted fabric is explored with self-made adhesive and anti-migrant a-gent. The optimum dyeing process is pigment less than 5 g/L, adhesive 15 g/L, anti-migrant agent 6 g/L, pick-up 50% -55%,pre-curing at 80 ℃ and curing at 170 ℃ for 1 min. The dyeings feature good levelness and satisfactory color fastness to washing and rubbing.%采用自制的黏合剂和防泳移剂对锦氨经编织物进行涂料连续轧染工艺试验.优化的染色工艺参数为:涂料用量≤5 g/L时,黏合剂15 g/L,防泳移剂6 g/L,轧余率50％～55％,预烘温度80℃,焙烘温度170℃,时间1 min.所染锦纶经编织物布面均匀,耐洗色牢度和耐摩擦色牢度能满足要求.
Loredo, Alexandre; 10.1016/j.jsv.2012.07.033
2012-01-01
In this paper, a plate model suitable for static and dynamic analysis of inhomogeneous anisotropic multilayered plates is described. This model takes transverse shear variation through the thickness of the plate into account by means of warping functions which are determined by enforcing kinematic and static assumptions at the layers interfaces. This model leads to a 10 x 10 behavior matrix in which membrane strains, bending curvatures, and transverse shear x and y-derivatives are coupled, and to a classical 2 x 2 shear behavior matrix. This model has been proven to be very efficient, especially when high ratios -up to 10E5- between the stiffnesses of layers are present. This work is related to Woodcock's model, so it can be seen as a reformulation of his work. However, it propose several enhancements: the displacement field is made explicit; it is reformulated with commonly used plate notations; laminate equations of motion are fully detailed; the place of this model relatively to other plate models is now e...
Probing Higgs-radion mixing in warped models through complementary searches at the LHC and the ILC
Frank, Mariana; Maitra, Ushoshi; Patra, Monalisa
2016-01-01
We consider the Higgs-radion mixing in the context of warped space extra dimensional models with custodial symmetry and investigate the prospects of detecting the mixed radion. Custodial symmetries allow the Kaluza-Klein excitations to be lighter, and protect Zbb to be in agreement with experimental constraints. We perform a complementary study of discovery reaches of the Higgs-radion mixed state at the 13 and 14 TeV LHC and at the 500 and 1000 GeV ILC. We carry out a comprehensive analysis of the most significant production and decay modes of the mixed radion in the 80 GeV - 1 TeV mass range, and indicate the parameter space that can be probed at the LHC and the ILC. There exists a region of the parameter space which can be probed, at the LHC, through the diphoton channel even for a relatively low luminosity of 50 fb^{-1}. The reach of the 4-lepton final state, in probing the parameter space is also studied in the context of 14 TeV LHC, for a luminosity of 1000 fb^{-1}. At the ILC, with an integrated luminos...
Gountas, Sandra; Gountas, John
2016-02-01
Much research focuses on organizational culture and its impact on customer orientation or emotional states and their impact on job satisfaction and well-being. This study aims to combine the complex roles of nurses' emotion states and job satisfaction in a model that identifies the effects of standards for service delivery (organizational culture), supervisor and co-worker support and the development of customer orientation. A previous study examined the relationships between nurses' personal resources, job satisfaction and customer orientation. This study examines how these variables relate to organizational standards and social support. A cross-sectional survey using a self-completion questionnaire with validated, existing scales to measure standards for service delivery, supervisor and co-worker support, job satisfaction, empathic concern, emotional exhaustion and customer orientation. Nurses (159) completed the questionnaire in 2010. The data were analysed using WarpPLS, a structural equation modelling software package. The results indicate that the final model fits the data well and explains 84% of the variance in customer orientation. The findings show the importance of standard for service delivery (organizational culture), supervisor and co-worker support on customer orientation. Nurses' personal resources interact with these, particularly supervisor and co-worker support, to develop staff job satisfaction and empathy. The need for support mechanisms in stressful times is discussed. We propose that training in compassion and empathy would help leaders to model desirable attributes that contribute towards customer orientation. © 2015 John Wiley & Sons Ltd.
Directory of Open Access Journals (Sweden)
Martin Frieß
2011-05-01
Full Text Available This study investigates the use of geometric morphometrics as well as methodological aspects specifically related to its application in paleoanthropology. Based on lateral photographs taken from a fossil sample of 58 specimens, a relative warps analysis was computed in order to assess the variation of cranial shape among various hominin groups. The fossil sample represents Middle and Late Pleistocene populations commonly assigned to H. erectus, H. neanderthalensis, archaic H. sapiens as well as anatomically modern H. sapiens. The preliminary results indicate that several fossil skulls considered as belonging to archaic H. sapiens have a distinct shape compared to modern humans. The results suggest that these hominins are not as closely related to modern humans as previously thought. Instead, their morphometric affinities suggest that they are as distinct from modern humans as are the Neandertals. Methodological aspects, such as raw data accuracy and the use of type 2 and 3 landmarks that are directly related to this type of quantitative analysis and that potentially affect their results, are discussed.
Wang, Gang-Jin; Xie, Chi; Han, Feng; Sun, Bo
2012-08-01
In this study, we employ a dynamic time warping method to study the topology of similarity networks among 35 major currencies in international foreign exchange (FX) markets, measured by the minimal spanning tree (MST) approach, which is expected to overcome the synchronous restriction of the Pearson correlation coefficient. In the empirical process, firstly, we subdivide the analysis period from June 2005 to May 2011 into three sub-periods: before, during, and after the US sub-prime crisis. Secondly, we choose NZD (New Zealand dollar) as the numeraire and then, analyze the topology evolution of FX markets in terms of the structure changes of MSTs during the above periods. We also present the hierarchical tree associated with the MST to study the currency clusters in each sub-period. Our results confirm that USD and EUR are the predominant world currencies. But USD gradually loses the most central position while EUR acts as a stable center in the MST passing through the crisis. Furthermore, an interesting finding is that, after the crisis, SGD (Singapore dollar) becomes a new center currency for the network.
Design and simulation study of axial warp-knitted fabrics%轴向经编针织物的设计与仿真
Institute of Scientific and Technical Information of China (English)
李秀丽; 丛洪莲
2012-01-01
为解决轴向经编针织物计算机辅助设计方面的不足以实现快速设计,对轴向经编针织物的CAD设计与仿真功能进行研究.在深入了解轴向经编针织物生产工艺的基础上,采用实验的方法测量了织物结构的尺寸,建立轴向经编针织物的CAD设计模型,其中包括地组织模型和铺纬组织模型；重点研究并建立了轴向经编针织物的纱线与线圈的二维仿真模型,以及玻璃纤维衬纱、线圈的三维仿真模型.以Visual C++为开发工具,并且结合OpenGL图形库,最终在WKCAD4.0系统中实现了轴向经编针织物的CAD设计与仿真功能.%In order to solve the problem of axial warp-knitted fabrics in computer aided design and realize fast designing, CAD design and simulation function of axial warp-knitted fabrics are studied. And on this basis an in-depth research of production process about axial warp-knitted fabrics is undertaken, the structural size of axial warp-knitted fabrics is measured, and CAD design models of these fabrics are built, including the ground structure model and weft structure model, with focuses on 2-D and 3-D simulation models of glass fiber yarn, loop, and laying-in yarn. With Visual C + + for development tools and combined with OpenGL graphics libraries, the CAD design and simulation functions of axial warp-knitted fabric are finally realized in the WKCAD4. 0 system.
Betancur, Julian; Simon, Antoine; Langella, Bernard; Leclercq, Christophe; Hernandez, Alfredo; Garreau, Mireille
2016-09-01
The synchronization and registration of dynamic computed tomography (CT) and magnetic resonance images (MRI) of the heart is required to perform a combined analysis of their complementary information. We propose a novel method that synchronizes and registers intrapatient dynamic CT and cine-MRI short axis view (SAX). For the synchronization step, a normalized cross-correlation curve is computed from each image sequence to describe the global cardiac dynamics. The time axes of these curves are then warped using an adapted dynamic time warping (DTW) procedure. The adaptation constrains the time deformation to obtain a coherent warping function. The registration step then computes the rigid transformation that maximizes the multiimage normalized mutual information of DTW-synchronized images. The DTW synchronization and the multiimage registration were evaluated using dynamic CT and cine-SAX acquisitions from nine patients undergoing cardiac resynchronization therapy. The distance between the end-systolic phases after DTW was used to evaluate the synchronization. Mean errors, expressed as a percentage of the RR-intervals, were 3.9% and 3.7% after adapted DTW synchronization against 10.8% and 11.3% after linear synchronization, for dynamic CT and cine-SAX, respectively. This suggests that the adapted DTW synchronization leads to a coherent warping of cardiac dynamics. The multiimage registration was evaluated using fiducial points. Compared to a monoimage and a two-image registration, the multiimage registration of DTW-synchronized images obtained the lowest mean fiducial error showing that the use of dynamic voxel intensity information improves the registration.
Schmidt, Matthew; Lo, Joseph Y; Grzetic, Shelby; Lutzky, Carly; Brizel, David M; Das, Shiva K
2015-08-01
Prior work by the authors and other groups has studied the creation of automated intensity modulated radiotherapy (IMRT) plans of equivalent quality to those in a patient database of manually created clinical plans; those database plans provided guidance on the achievable sparing to organs-at-risk (OARs). However, in certain sites, such as head-and-neck, the clinical plans may not be sufficiently optimized because of anatomical complexity and clinical time constraints. This could lead to automated plans that suboptimally exploit OAR sparing. This work investigates a novel dose warping and scaling scheme that attempts to reduce effects of suboptimal sparing in clinical database plans, thus improving the quality of semiautomated head-and-neck cancer (HNC) plans. Knowledge-based radiotherapy (KBRT) plans for each of ten "query" patients were semiautomatically generated by identifying the most similar "match" patient in a database of 103 clinical manually created patient plans. The match patient's plans were adapted to the query case by: (1) deforming the match beam fluences to suit the query target volume and (2) warping the match primary/boost dose distribution to suit the query geometry and using the warped distribution to generate query primary/boost optimization dose-volume constraints. Item (2) included a distance scaling factor to improve query OAR dose sparing with respect to the possibly suboptimal clinical match plan. To further compensate for a component plan of the match case (primary/boost) not optimally sparing OARs, the query dose volume constraints were reduced using a dose scaling factor to be the minimum from either (a) the warped component plan (primary or boost) dose distribution or (b) the warped total plan dose distribution (primary + boost) scaled in proportion to the ratio of component prescription dose to total prescription dose. The dose-volume constraints were used to plan the query case with no human intervention to adjust constraints during
Institute of Scientific and Technical Information of China (English)
刘炉; 刘相果; 李瑞峰; 徐莉萍; 陶骏
2013-01-01
Based on the main factors resulting in NC milling errors of piezo-jacquard guide bar used on 230 warp knitting machine,the NC milling techniques of long and thin workpieces affecting machining quality in the manufacture process,such as machining path,cutting strategy,fixing workpieces and cutting parameters were analyzed. The techniques and technological ways of controlling deformation and improving milling precision and surface quality were proposed. The results showed that the milling precision and the surface quality requirement was reached because of the milling technique of piezo-jacquard guide bar.%针对230"经编机压电贾卡梳栉数控铣削加工误差产生的主要原因,分析了该类超长细薄零件数控铣削加工过程中涉及到的工艺路线、走刀策略、工件装夹及切削参数等对加工质量的影响,提出了减小贾卡梳栉的数控铣削加工变形,提高其加工精度和表面质量的工艺措施.实验结果表明,采用该文提出的贾卡梳栉铣削工艺,零件的加工精度及表面粗糙度均达到了使用要求.
Revealing Asymmetries in the HD 181327 Debris Disk: A Recent Massive Collision or ISM Warping
Stark, Christopher C; Weinberger, Alycia J; Debes, John H; Grady, Carol A; Jang-Condell, Hannah; Kuchner, Marc J
2014-01-01
New multi-roll coronagraphic images of the HD 181327 debris disk obtained using the Space Telescope Imaging Spectrograph (STIS) on board the Hubble Space Telescope (HST) reveal the debris ring in its entirety at high S/N and unprecedented spatial resolution. We present and apply a new multi-roll image processing routine to identify and further remove quasi-static PSF-subtraction residuals and quantify systematic uncertainties. We also use a new iterative image deprojection technique to constrain the true disk geometry and aggressively remove any surface brightness asymmetries that can be explained without invoking dust density enhancements/deficits. The measured empirical scattering phase function for the disk is more forward scattering than previously thought and is not well-fit by a Henyey-Greenstein function. The empirical scattering phase function varies with stellocentric distance, consistent with the expected radiation pressured-induced size segregation exterior to the belt. Within the belt, the empiric...
Time-Frequency Analysis Using Warped-Based High-Order Phase Modeling
Directory of Open Access Journals (Sweden)
Ioana Cornel
2005-01-01
Full Text Available The high-order ambiguity function (HAF was introduced for the estimation of polynomial-phase signals (PPS embedded in noise. Since the HAF is a nonlinear operator, it suffers from noise-masking effects and from the appearance of undesired cross-terms when multicomponents PPS are analyzed. In order to improve the performances of the HAF, the multi-lag HAF concept was proposed. Based on this approach, several advanced methods (e.g., product high-order ambiguity function (PHAF have been recently proposed. Nevertheless, performances of these new methods are affected by the error propagation effect which drastically limits the order of the polynomial approximation. This phenomenon acts especially when a high-order polynomial modeling is needed: representation of the digital modulation signals or the acoustic transient signals. This effect is caused by the technique used for polynomial order reduction, common for existing approaches: signal multiplication with the complex conjugated exponentials formed with the estimated coefficients. In this paper, we introduce an alternative method to reduce the polynomial order, based on the successive unitary signal transformation, according to each polynomial order. We will prove that this method reduces considerably the effect of error propagation. Namely, with this order reduction method, the estimation error at a given order will depend only on the performances of the estimation method.
Warping transform of the refractive normal mo de in a shallow water waveguide%浅海波导中折射类简正波的warping变换∗
Institute of Scientific and Technical Information of China (English)
戚聿波; 周士弘; 张仁和
2016-01-01
In a shallow water waveguide, the low-frequency acoustic field can be viewed as a sum of normal modes. Warping transform provides an effective tool to filter the normal modes from the received signal of a single hydrophone, which can be used for source ranging and geoacoustic inversion. However, it should be noted that the conventional warping operator h(t)=√t2+t2r is only valid for a signal consisting of reflection dominated modes, where r represents the source range. In a waveguide with a strong thermocline or a surface channel where refracted modes dominate the received sound field, the dispersive characteristics of the waveguide become different and the performance of the warping operator h(t) = √t2+t2r will be significantly degraded. In this paper, the dispersive characteristics and warping transform of the refractive normal modes in a waveguide with a linearly decreased sound speed profile are discussed. The formulae for the horizontal wavenumber, the phase in frequency domain and the instantaneous phase in time domain of the refractive mode are deduced. Based on these formulae, the time warping and frequency warping operators verified by the simulated data are presented. Through time-axis stretching or compression, the time warping operator h(t)=tr−t−2, where tr = r/c(h) and c(h) represents the bottom sound speed, can transform the refracted modes into single-tone components of frequencies determined by source range, sound speed gradient of water, bottom sound speed and mode number. The frequency warping operator h(f)=Df3, where D is a constant, can transform the refracted modes into separable impulsive sequences through frequency-axis stretching or compression and the time delay of the impulsive sequences changes linearly with the source range. As the warped modes are separated in time domain or frequency domain, these two operators can be used for filtering the refracted normal modes from the received signal. The theories in this paper are also
Experimental techniques; Techniques experimentales
Energy Technology Data Exchange (ETDEWEB)
Roussel-Chomaz, P. [GANIL CNRS/IN2P3, CEA/DSM, 14 - Caen (France)
2007-07-01
This lecture presents the experimental techniques, developed in the last 10 or 15 years, in order to perform a new class of experiments with exotic nuclei, where the reactions induced by these nuclei allow to get information on their structure. A brief review of the secondary beams production methods will be given, with some examples of facilities in operation or under project. The important developments performed recently on cryogenic targets will be presented. The different detection systems will be reviewed, both the beam detectors before the targets, and the many kind of detectors necessary to detect all outgoing particles after the reaction: magnetic spectrometer for the heavy fragment, detection systems for the target recoil nucleus, {gamma} detectors. Finally, several typical examples of experiments will be detailed, in order to illustrate the use of each detector either alone, or in coincidence with others. (author)
Spoken Language Identification Using Hybrid Feature Extraction Methods
Kumar, Pawan; Mishra, A N; Chandra, Mahesh
2010-01-01
This paper introduces and motivates the use of hybrid robust feature extraction technique for spoken language identification (LID) system. The speech recognizers use a parametric form of a signal to get the most important distinguishable features of speech signal for recognition task. In this paper Mel-frequency cepstral coefficients (MFCC), Perceptual linear prediction coefficients (PLP) along with two hybrid features are used for language Identification. Two hybrid features, Bark Frequency Cepstral Coefficients (BFCC) and Revised Perceptual Linear Prediction Coefficients (RPLP) were obtained from combination of MFCC and PLP. Two different classifiers, Vector Quantization (VQ) with Dynamic Time Warping (DTW) and Gaussian Mixture Model (GMM) were used for classification. The experiment shows better identification rate using hybrid feature extraction techniques compared to conventional feature extraction methods.BFCC has shown better performance than MFCC with both classifiers. RPLP along with GMM has shown be...
Transmission Mechanism Analysis of Let-off System on Warp Knitting Machine%经编送经系统的传动机构分析
Institute of Scientific and Technical Information of China (English)
朱克来; 夏风林
2015-01-01
Electrical beam control system transmission used on warp knitting are divided into two types, in-cluding worm and multi-stage gear. The drive principle and the let-off accuracy influence of worm and multi-stage gear were analyzed, and two kinds of warp system deviation rate were experimentally measured. The results show that, worm transmission has a better precision than multi-stage gear transmission; when the beam-warping shape is well, the deviation of beam perimeter have less effect on deviations of let-off precision; good production environ-ment and checked regularly the drive status of worm and gear have a certain impact on let-off precision.%经编机上的电子送经系统一般有蜗轮蜗杆式和多级齿轮式两类传动形式，分析这两种传动机构的工作原理及其对送经精度的影响，并通过试验测试两种送经系统传动下的送经量偏差率。结果表明：蜗轮蜗杆传动比多级齿轮传动送经有更高的精度；当整经成形良好时，经轴的周长偏差对送经精度的偏差影响较小，对织物品种的影响也较小；良好的生产环境以及定期检查蜗轮蜗杆和齿轮的传动状况都有利于提高送经精度。
Application and Development of Industrial Warp-knitted Fabric%产业用经编针织物的应用与发展
Institute of Scientific and Technical Information of China (English)
蒋高明; 高哲
2014-01-01
As one of important categories of textiles, industrial warp-knitted fabric has great development potential and has become the new development direction of technical textiles sector. By introducing the characteristics and advantages of this kind of product, the paper discussed the latest applications of warp-knitted fabric in the fields of energy, aerospace and aviation, architecture, medical and land transportation. The problems existing in the development of the industrial warp-knitting sector were summarized. It also give suggestions on R&D, personnel training, platform construction and opening up new application fields, aimed at promoting the healthy and well-organized development of the industry.%产业用经编针织物作为重要的纺织品类型之一，以其可设计性强和应用领域广泛等特点，极具发展潜力，逐渐成为产业用纺织品行业创新发展的主要方向。文章从应用特点与优势等方面，阐述了产业用经编针织物在能源、航空航天、建筑、医疗以及陆路交通等多个领域的最新应用；分析总结了行业发展存在的问题；从研发、人才培养、平台建设和新领域开发等4个方面提出建议，以使我国产业用经编针织物行业实现健康、有序的发展。
Shirakawa, Akiko
This thesis consists of three parts. In the first part, we study the magnetically driven precession of warped disks. An accretion disk around a rotating magnetized star is subjected to the magnetic torques that induce warping and precession of the disk. We study the global hydrodynamical warping/ precession modes of the disk under the combined influences of the magnetic torques, relativistic frame dragging, and the classical precession due to oblateness of the neutron star. We apply our analysis to two types of accreting systems: low-mass X-ray binaries (LMXBs) and accreting X-ray pulsars. We argue that some features of low-frequency quasi-periodic oscillations (QPOs) in LMXBs and milli-Hertz QPOs in accreting X-ray pulsars can be explained by the magnetically driven precession of warped disks. The second part is related to the hydrodynamically-driven mechanism for asymmetric supernova explosions/neutron star kicks. We explore the possibility that the gravity modes in the core of a presupernova star may be amplified in the silicon burning shell to produce the global asymmetric perturbations that lead to an asymmetric supernova explosion. By performing a linear analysis of the oscillations in the cores of presupernova stars, we estimate the growth/ damping rates of the modes. We find that most of the modes are damping modes with a few exceptions. We also find that, even for a growing mode, the timescale of mode growth is much longer than the remaining time before the core collapse. We conclude that the gravity modes in a presupernova core cannot provide the global asymmetric perturbations that lead to an asymmetric supernova explosion. In the last part, we attempt to predict the innate chemical composition of a neutron star atmosphere. There has been great progress in X-ray observations and now thermal radiation from neutron stars is being studied in detail. There has also been significant progress in modeling thermal spectra from neutron stars. However, the unknown
Institute of Scientific and Technical Information of China (English)
刘忧华
2015-01-01
The structure and function of air-jet looms warp loosening device was introduced , and analyzed the function of co-ordination between Warp loosening device and the back rest for Air Jet loom. It can be stable equilibrium in the process of weaving warp tension to reduce the tension fluctuation for wealing.%介绍了喷气织机松经装置的结构及作用，分析了后梁和松经装置的配合使用，可在织造过程中稳定均衡经纱张力，减少张力的波动，以利于织造的进行。
Directory of Open Access Journals (Sweden)
Slamet Riyadi
2011-01-01
Full Text Available The use of image processing technique for cardiac motion analysis has been an active research in the past decade. The estimation of myocardial motion eases the cardiologist in diagnosing cardiac abnormalities. In term of movement analysis, optical flow is the most popular technique that has been used by researchers. This paper describes the implementation and evaluation of three optical flow computation techniques to estimate the myocardial motion using echocardiographic images. The three techniquesare the global smoothness method (GSM, the local smoothness method (LSM and warping technique (WT. Optical flow field is computed based on healthy cardiac video on parasternal short axes view. These techniques look promising since the optical flow fields can be utilized to estimate the myocardial movement and comply with its true movement. The performances of each technique in terms of the direction, homogeneity and computing time, are also discussed.
Simulation and analysis of warp tension based on virtual prototyping%基于虚拟样机技术的经纱张力仿真与分析
Institute of Scientific and Technical Information of China (English)
邱海飞; 王益轩
2011-01-01
The reasons that cause warp tension are analyzed. The virtual prototype model for warp tension is set up in SolidWorks software. The plain woven fabric is made as object to study, the dynamic simulation and analysis of the stretch tension, vertical tension and horizontal tension of the warp are carried out in COSMOSMotion. Then the law of the warp tension varies during weaving is acquired, and the methods of decomposition and computation of warp tension in dynamic and changing process are put forward. In order to offer a foundation for shedding design, the maximum of warp tension is studied and its distribution characteristic and changing law are obtained by statistical analysis, then analytical comparison between the simulated results and the values measured is made.%为深入分析经纱张力产生的因为,在SolidWorks软件中创建经纱张力虚拟样机仿真模型.以平纹织物为研究对象,在COSMOSMotion模块中分别对经纱的拉伸张力、垂直张力和水平张力进行动态仿真与分析,获得织造过程中经纱张力的变化规律,并提出经纱张力在动态变化过程中的分解方法和计算方法.探讨了经纱张力的最大值.通过统计分析得出经纱张力最大值的分布特点和变化规律.另将仿真结果与实测结果做了比较与分析,可为梭口形状的设计提供参考.
The Wide Range of Hot Dust Emission from Quasars: Clumpy Tori, Warped Disks and Black Hole Feeding
Elvis, Martin
Objectives: Quasars and AGNs show characteristic hot dust emission not seen in other objects. This is due to an obscuring "torus" in the inner regions of the quasar. Understanding of this "torus" has progressed slowly in the past 2+ decades. Based on our WISE-based pilot project we find a wide range of IR (dust) to optical (accretion disk) emission ratios in quasar spectral energy distributions (SEDs). This implies order of magnitude differences in the covering factor of the obscuring "torus" from object to object. Moreover the near- IR (hot dust) to mid-IR (warm dust) ratio varies by a similar factor, so the structure within the "torus" also varies greatly from object to object. The results will inform us not only about the inner structure of quasars, but also of the mechanism that brings matter into bound orbit around the central supermassive black hole (SMBH). Methods: We propose to analyze the WISE data for 24,257 SDSS broad emission line, type 1, quasars that also lie in the near-IR UKIDSS survey to produce optical-mid-IR SEDs. The properties of the dust-emitting region will be our primary focus. Previous samples have been limited to a few hundred quasar SEDs. With this large sample we can search for systematic SED changes with redshift, luminosity and with physical parameters derived from the SDSS spectra: black hole mass and Eddington ratio. We will use the 'mixing diagram' method developed for COSMOS, plus theory based clumpy torus and warped disk models. Significance: The growth of supermassive black holes is a central part of galaxy evolution and cosmology, yet is poorly understood. The "torus" is likely the resevoir from which the accretion disk is fed, but how it forms is unknown. Moreover AGN "feedback" is thought to have a major effect on the evolution of galaxies, regulating star formation. However, the influence of the central AGN on its host galaxy is limited if the "torus" intercepts most of AGN continuum, or blocks accretion disk winds. Our
牡丹江市区平翘舌发音情况%Mudanjiang city flat become warped tongue pronunciation
Institute of Scientific and Technical Information of China (English)
姜伟杰
2015-01-01
牡丹江市区平翘舌的研究是一项音系变异的研究,研究的是老派和新派变异现象.这里涉及的是显像时间的研究,我们同时观察不同年龄段的人发平翘舌音的表现,以了解现在的语言变化,它所体现在几代人的言语特点上的一个语言变体的发展趋势.%Mudanjiang city flat become warped of the research is a sound system variation of the tongue, is the study of the old and new mutation phenomenon. Here involves imaging time study, we observe people of different ages to send flat at the same time become warped lingual expression, now to learn the language of change, it embodied in the words of generations characteristics on the variation trend of the development of a language.
Directory of Open Access Journals (Sweden)
Long Jiao
2015-01-01
Full Text Available The application of automated correlation optimized warping (ACOW to the correction of retention time shift in the chromatographic fingerprints of Radix Puerariae thomsonii (RPT was investigated. Twenty-seven samples were extracted from 9 batches of RPT products. The fingerprints of the 27 samples were established by the HPLC method. Because there is a retention time shift in the established fingerprints, the quality of these samples cannot be correctly evaluated by using similarity estimation and principal component analysis (PCA. Thus, the ACOW method was used to align these fingerprints. In the ACOW procedure, the warping parameters, which have a significant influence on the alignment result, were optimized by an automated algorithm. After correcting the retention time shift, the quality of these RPT samples was correctly evaluated by similarity estimation and PCA. It is demonstrated that ACOW is a practical method for aligning the chromatographic fingerprints of RPT. The combination of ACOW, similarity estimation, and PCA is shown to be a promising method for evaluating the quality of Traditional Chinese Medicine.
Design of Clamping Device on Warp Beam%经编机用盘头夹紧装置的设计
Institute of Scientific and Technical Information of China (English)
解朝晖
2015-01-01
现有的靠机械刚性螺纹并紧方式设计的盘头,当纱线减少到一定程度时,将会发生经轴打滑现象,须人工调整,否则将会在编织的织物上产生横条或隐横条. 针对这一问题,提出采用蝶形弹簧开发一种盘头自动夹紧装置,并介绍了蝶形弹簧设计的要求及计算方法.实践证明,该新式夹紧装置可解决一般夹紧装置不方便和可靠性差的问题,具有一定的实用价值.%For the current warp beam tightened only by simple rigidity of screw thread, when the yarn on that beam reduces to a certain extent, slipping phenomenon will happen, and then it needs manual adjustments. If not, horizontal stripe or hidden stripes will appear on the knitted fabric. Concerning this issue, this paper proposes a clamping device on warp beam based on the belleville spring,and introduces its design requirements and calculation methods. This kind of beam developed in this paper proves to be convenient, reliable and practical.
The warp tension controlling system of towel rapier weaving machine%毛巾剑杆织机的经纱张力控制系统
Institute of Scientific and Technical Information of China (English)
章玉铭
2011-01-01
针对传统毛巾织机经纱张力控制效率低、误差大等问题,基于计算机技术、传感器技术、伺服技术设计了毛巾剑杆织机的经纱张力控制系统.该系统实现了毛巾剑杆织机的电子卷取、电子送经的精确控制,确保在同一织物中采用不同纬密时实时快速地把张力调整到目标值.%To solve the problems existing in the warp tension controlling system of traditional towel rapier weaving machine, such as poor efficiency, big error and so on, the warp tension controlling system of towel rapier weaving machine is designed. With the help of computer technology and sensor technology as well as servo technology , a precise controls of electronic let-off and take-up are realized, which ensures that the tension is adjusted to the design value real-timely and rapidly when the same fabric is woven under different weft densities.
Development and application of high-gauge warp-knitted spacer fabric%超大隔距经编间隔织物的开发与应用
Institute of Scientific and Technical Information of China (English)
张晓会; 马丕波; 缪旭红
2016-01-01
介绍超大隔距经编间隔织物的定义、成形技术和编织原理，并与传统经编间隔织物进行对比；同时，结合经编间隔织物的发展前景，重点阐述超大隔距经编间隔织物在医疗救护、运动娱乐和国防军事等领域内的产业优势和应用前景。%The definition , forming technology and weaving principles of high-gauge warp-knitted spacer fabric were introduced and compared with traditional warp-kintted spacer fabric . And according to the development prospect of warp-kintted spacer fabric , the high-gauge warp-knitted spacer fabric 's industrial advantages and application prospect in the fields of medical aid , sports and entertainment , national defense and military affairs , were stated .
A Vertical Resonances of G-Mode Oscillations in Warped Disks and QPOs in Low-Mass X-Ray Binaries
Kato, S
2005-01-01
Resonant oscillations in warped disks are examined in order to explain high-frequency QPOs and horizontal-branch QPOs in low-mass X-ray binaries. Different from our previous work, addressed to the same subjects, we relax in this paper the assumption that the disks are isothermal in the vertical direction. That is, the pressure, density, and temperature are assumed to be distributed in the vertical direction with a polytropic relation, and the polytropic index changes as the disk state changes. By this generalization and by some subsidiaries we can qualitatively explain, within the framework of our resonance model, observed large frequency variations in neutron-star QPOs and little variations in black-hole QPOs. We consider vertical resonances of g-mode oscillations, since they are most appropriate to explain observations.
Investigation on Sound Absorption Properties of Warp-Knitted Spacer Fabric%经编间隔织物的吸声性能研究
Institute of Scientific and Technical Information of China (English)
粱丽娟; 龙海如
2011-01-01
采用阻抗管传递函数法测试了5种不同规格经编间隔织物在声频为100～2 500 Hz时的吸声系数,分析了织物结构参数对吸声性能的影响,并比较了该织物与常用吸声、衬垫材料海绵在吸声性能方面的差异.研究结果表明:织物的吸声性能与织物的密度、厚度、孔隙率等参数有关；经编间隔织物的吸声性能优于同厚度的海绵,在汽车行业中将是海绵类产品的优异替代品.%The sound absorption coefficient (SAC) of five warp-knitted spacer fabrics with different specifications under the frequency of 100-2 500 Hz are tested in a impedance tube by transfer function method. The effect of the structural parameters on sound absorption properties is analyzed, and the differences in the sound absorption performance between spacer fabrics and the sponge with similar thickness are compared. The research results indicate that the sound absorption properties of the fabric are related to its structural parameters, such as thickness, density, porosity rate and so on. The sound absorption of spacer fabric is superior to sponge with the same thickness. Therefore, warp-knitted spacer fabric is the good alternatives of sponge in the automobile industry.
Institute of Scientific and Technical Information of China (English)
李筱一; 缪旭红; 杨大伟; 赵帅权
2016-01-01
从经编鞋面成形工艺和双色效应形成方法入手，在双针床贾卡经编机上设计经编间隔双色成形鞋面，详细阐述成形鞋面的编织工艺步骤，包括原料选择、组织设计、贾卡设计、排版设计，以及编织要点等。并在RDPJ5/1型双针床经编机上开发一款新型的经编间隔双色成形鞋面材料，给出设备参数、上机工艺参数、成品工艺等。该成形鞋面材料具有良好的舒适性和功能性，其双色效应提高了鞋面美观性，为双色运动鞋面材料的开发与应用提供参考。%This paper designed a double colored fully-fashiond vamp by warp knitted spacer fabric on double-bed jacquard warp knitting machine in terms of the technology of warp knitting vamp, the formation methods of double colored effect and some other aspects, then it introduced in detail the warp knitting procedure of fully-fash-ioned vamp, including raw material selection, pattern design, jacquard design, layout design, key points of design and so on. It developed a new kind of double colored fully-fashioned vamp by warp knitted spacer fabric on RD-PJ5/1 double needle bed warp knitting machine including machine parameters, technological parameters for machine operation, product process etc. The fully-fashioned vamp has good performance in comfort and functionality, and the double colored effect improved the aesthetics of vamp. This paper provides the reference for the development and application of the double colored sports vamp fabrics.
On N = 2 compactifications of M-theory to AdS{sub 3} using geometric algebra techniques
Energy Technology Data Exchange (ETDEWEB)
Babalic, E. M.; Coman, I. A.; Condeescu, C.; Micu, A. [IFIN-HH, Department of Theoretical Physics, 077125 Magurele (Romania); Lazaroiu, C. I. [IFIN-HH, Department of Theoretical Physics, 077125 Magurele, Romania and IBS, Center for Geometry and Physics, and POSTECH, Department of Mathematics, Pohang, Gyeongbuk 790-784 (Korea, Republic of)
2013-11-13
We investigate the most general warped compactification of eleven-dimensional supergravity on eight-dimensional manifolds to AdS{sub 3} spaces (in the presence of non-vanishing four-form flux) which preserves N = 2 supersymmetry in three dimensions. Without imposing any restrictions on the chirality of the internal part of the supersymmetry generators, we use geometric algebra techniques to study some implications of the supersymmetry constraints. In particular, we discuss the Lie bracket of certain vector fields constructed as pinor bilinears on the compactification manifold.
DEFF Research Database (Denmark)
Lunde Nielsen, Espen; Halse, Karianne
2013-01-01
Acquired Techniques - a Leap into the Archive, at Aarhus School of Architecture. In collaboration with Karianne Halse, James Martin and Mika K. Friis. Following the footsteps of past travelers this is a journey into tools and techniques of the architectural process. The workshop will focus upon...... architectural production as a conglomerate of various analogue and digital methods, and provide the basics, the tips/tricks - and how the tool themselves becomes operational for spatial/thematic investigations. Eventually, this will become a city, exhibition and phamplet inhabited by the (by...
Directory of Open Access Journals (Sweden)
Marcia Pinheiro
2015-05-01
Full Text Available In this paper, we discuss three translation techniques: literal, cultural, and artistic. Literal translation is a well-known technique, which means that it is quite easy to find sources on the topic. Cultural and artistic translation may be new terms. Whilst cultural translation focuses on matching contexts, artistic translation focuses on matching reactions. Because literal translation matches only words, it is not hard to find situations in which we should not use this technique. Because artistic translation focuses on reactions, judging the quality of an artistic translation work is one of the most difficult things one can do. We end up having a score of complexity and humanity for each one of the mentioned techniques: Literal translation would be the closest thing we have to the machines world and artistic translation would be the closest thing we have to the purely human world. By creating these classifications and studying the subtleties of each one of them, we are adding degrees of quality to our courses and to translation as a professional field. The main contribution of this paper is then the formalization of such a piece of knowledge. We, however, also lay the foundations for studies of this type.
Engelfried, J
1999-01-01
In this course we will give examples for experimental techniques used in particle physics experiments. After a short introduction, we will discuss applications in silicon microstrip detectors, wire chambers, and single photon detection in Ring Imaging Cherenkov (RICH) counters. A short discussion of the relevant physics processes, mainly different forms of energy loss in matter, is enclosed.
DEFF Research Database (Denmark)
Jacobsen, Finn
2008-01-01
The Handbook of Signal Processing in Acoustics will compile the techniques and applications of signal processing as they are used in the many varied areas of Acoustics. The Handbook will emphasize the interdisciplinary nature of signal processing in acoustics. Each Section of the Handbook...... will present topics on signal processing which are important in a specific area of acoustics. These will be of interest to specialists in these areas because they will be presented from their technical perspective, rather than a generic engineering approach to signal processing. Non-specialists, or specialists...... from different areas, will find the self-contained chapters accessible and will be interested in the similarities and differences between the approaches and techniques used in different areas of acoustics....
Energy Technology Data Exchange (ETDEWEB)
Chen, Gang; Lin, Yuehe
2008-07-20
Sensitive and selective detection techniques are of crucial importance for capillary electrophoresis (CE), microfluidic chips, and other microfluidic systems. Electrochemical detectors have attracted considerable interest for microfluidic systems with features that include high sensitivity, inherent miniaturization of both the detection and control instrumentation, low cost and power demands, and high compatibility with microfabrication technology. The commonly used electrochemical detectors can be classified into three general modes: conductimetry, potentiometry, and amperometry.